The History of Determination of Bio-Antioxidants and Neuromediators by GC- and GC-MS Techniques (Translational Lecture Course Summary)

This introductory review examines the historical and methodological aspects and prospects for the application of gas chromatography in redox biology and neurochemistry. In particular, the following topics are covered: the history of gas chromatography and GC-MS of thiols; the history of gas chromatography and GC-MS of acetylcysteine; the history of gas chromatography and GC-MS of acetylcholine; the history of gas chromatography and GC-MS of catecholamines and their metabolites; the history of gas chromatography and GC-MS of hydroperoxides; and the history of gas chromatography and GC-MS of phosphatidylcholine.

Keywords: Gas chromatography, Thiols, Acetylcysteine, Acetylcholine, Catecholamines, Hydroperoxides, Phosphatidylcholine, GC-MS, Antioxydants, Bio-antioxydants, Redox-etiology, Redox-pathology, Neuromediators, Neurotransmitters

1. The Practical Importance of Analytical Determination of Antioxidants
This article draws on several previously unpublished bibliographic compilations and seminar materials prepared over roughly a decade. The core foundation consists of annotated working lists on chromatographic methods for neurotransmitters, antioxidant chemistry and neurochemical applications of gas chromatography and GC–MS, assembled at different stages of the second author’s academic and laboratory work (from pre-graduation research through 2016) and later expanded in the early 2020s with contributions from all co-authors. Each set of documents provided a defined share of the present bibliography and conceptual outline, with the largest inputs coming from neurotransmitter-focused chromatography and GC–MS surveys accumulated during dissertation-related work and subsequent employment in research laboratories.

The preparation history also reflects the institutional and technical constraints under which the material was collected. Multiple research initiatives were interrupted by contract termination, laboratory reorganization, dissolution of units following broader institutional reforms and progressive obsolescence and loss of GC/GC–MS instrumentation and facilities. An updated integrative bibliographic dossier produced for internal planning in the early 2020s ultimately remained unused due to further relocations and degradation of laboratory infrastructure. Given the accelerating loss of technical capacity and the improbability of converting the accumulated bibliographic groundwork into new experimental GC/GC-MS studies, the authors decided to publish the present abridged review version as the most feasible outcome under current conditions, without attempting to expand it into a full-scale high-impact review.
 

A major practical challenge associated with the medical use of various antioxidants¹ is their detection in natural samples^2,3, pharmaceutical substances and their precursors^4,5, as well as in human tissues and physiological excreta. Without documenting the redox status of the latter, the transition from redox biology^6-9 to redox medicine^10-14 cannot be meaningfully advanced. This implies that, in the absence of objective assessment of redox status, a constructive approach to redox pathology^15-20, redox aetiology^21,22 and redox-based disease prevention^23,24-achieved through dietary intake of antioxidant-containing foods and supplements^25-37-is likewise unattainable.

Clearly, if agents acting as antioxidants in metabolism cannot be analytically monitored, their tissue levels cannot be regulated, nor-ideally-can the antioxidant-induced status of cells and tissues be controlled, at least with the aim of reaching a range of optimal concentrations associated with predictable physiological effects^38-40. Therefore, technologies in the analytical chemistry of antioxidants^41-45 and, in particular, in the analytical biochemistry of antioxidants^46-48 are of critical importance for formulating problems in redox medicine. At the same time, many methods used for these purposes quantify activity rather than specific chemical systems that are selective with respect to composition and reactivity in a given medium. Examples include potentiometric determination of redox-active species (in particular radical species⁴⁹) and antioxidants^50-54.

If one accepts that many antioxidant schemes operate efficiently in microheterogeneous/ultramicroheterogeneous media⁵⁵ and that biological tissue containing organelles with different electrophysical parameters represents a highly characteristic example of such media, it becomes evident that additive analysis, as well as evaluation based on overall redox efficiency, is unfortunately insufficiently rigorous for the purposes of redox medicine. At a minimum, the concentrations of different redox components and antioxidants must be assessed separately; at a maximum, the analysis should be position-sensitive-performed within the compartments in which the reaction processes occur-regardless of whether plant or animal tissues are considered^56-65.

The second task pertains to classical cytochemistry or ultrastructural biochemistry and is therefore not considered here, whereas the first task is relatively straightforward from the standpoint of point measurements or sample-averaged determinations-i.e., it can be addressed using standard methods of bioanalytical chemistry^66-72. In particular, since the early 2000s, gas-chromatographic methods for antioxidants^73-87-most actively developed in the context of GC–MS, against which other gas-chromatographic techniques “fade, losing their classical luster”^88,89-may be regarded as an optimal means of achieving such analytical objectives. Nevertheless, classical gas-chromatographic techniques can also be employed for these purposes, as will be shown below.

2. On “dialectical mechanisms” in Redox Physiology

At the same time, even under this simplified approach, the chemical physics of molecular–biological regulatory systems remain unchanged, constituting a dialectical^90-99 reflection of the mechanisms underlying the corresponding physiological and biochemical reactions. For example, for the well-known thiols, pro-oxidant and antioxidant effects coexist^100-109. The recently cited study¹⁰⁸ demonstrates that the pro-oxidant effects of native thiols are associated with reactions of thiyl radicals, which readily add to unsaturated bonds; these radicals are formed, in particular, in thiol exchange reactions with other radicals and during thiol interactions with hydroperoxides.

At the same time, in solution at physiological temperature, the antioxidant mechanisms of endogenous thiols (glutathione, cysteine, homocysteine) include reactions with reactive oxygen species-peroxyl radicals (and hydrogen peroxide); notably, reduction of the latter (hydrogen peroxide) is accompanied by radical formation. The phenolic antioxidants used in the aforementioned work (resveratrol and caffeic acid) are consumed upon interaction with glutathione and the reaction is accelerated in the presence of hydrogen peroxide. Thus, thiols provide an example that illustrates the full range of antagonistic and competitive, as well as cooperative and synergistic, processes characteristic of the chemistry of such systems-excluding those determined by additional phases and compartmentalizing boundaries. For solution chemistry and the chemistry of homogeneous media (both aqueous and non-aqueous^110,111), this is sufficient.

3. Excursus into the Chemistry of Microheterogeneous Systems and Membrane Mimetics

For the chemistry of microheterogeneous systems, the situation appears even more complex^112-117, both in terms of solute behavior in micelles and in terms of photometric and spectrophotometric determination, as well as chromatography and chromatography–mass spectrometry of such systems-procedures that become almost impossible without disrupting the microheterogeneous structure. In other words, the method ceases, to any meaningful extent, to qualify as non-destructive, owing to the emergent properties of microheterogeneous assemblies and the irreducibility of those properties to the behavior of the individual components.

In our work, the principal practical sources concerning the behavior of the microheterogeneous systems of interest are publications from the Laboratory of Liquid-Phase Oxidation of the N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, which effectively continues the research tradition in homolytic reactions established by Academician N.M. Emanuel and his colleagues. This laboratory provides a bridge to several aspects that are largely beyond the scope of the present review but are important for understanding the neurochemical dimension of phenomena involving neurotransmitters/neuromediators, in particular:

·                  The influence of membrane lipids on free-radical generation in acetylcholine-containing systems¹¹⁸

·                  The combined (superadditive, microstructure-dependent) contributions of lipids/surfactants and antioxidants in similar microheterogeneous systems^119,120;

·                  The interactions of thiols and catecholamines with reactive oxygen species¹²¹;

·                  Catalysis of radical reactions in mixed surfactant micelles in the presence of hydroperoxides.

·                  This line of research has a broader physicochemical context. In¹²², the authors note that:

o        In oxidizing hydrocarbons (RH), hydroperoxides (ROOH)-the primary amphiphilic oxidation products—form mixed micelles with cationic surfactants, {m\mathrmROOH⋯ n\mathrmCS⁺}, in which ROOH decomposition into radicals is accelerated and in which other polar components (metal compounds, inhibitors, etc.) may become concentrated; this substantially affects both the rate and the mechanism of oxidation. It is shown that cationic surfactants immobilized on a solid support retain the ability to catalyze hydroperoxide decomposition with radical formation and to initiate radical oxidation and polymerization processes.

o        The specific features of the catalytic action of cationic surfactants, in combination with hydroperoxides, on radical generation are considered, as is the influence of various factors on this process, including transition-metal compounds, oxygen and an external magnetic field.

·                  These considerations are applicable to neurotransmitter-containing systems, including, specifically, acetylcholine-containing systems. Thus,^119,120 reports that:

·               Cationic surfactants (S⁺) and acetylcholine (ACh; a major neurotransmitter that plays a substantial role in the neuromuscular and cognitive activity of living organisms) form mixed reverse micelles with hydroperoxides (ROOH) in organic media, in which the catalytic decomposition of ROOH into free radicals is accelerated.

·                The addition of cholesterol (Chol; 30 mol%) to pyridinium bromides (CPB) and cetyltrimethylammonium bromide (CTAB) reduces, by several-fold, the rate of radical generation during the catalytic decomposition of ROOH.

·                  …in the case of less ordered and larger reverse micelles ACh–ROOH, an increase in the rate of radical initiation is observed.

·                  The addition of Chol has virtually no effect on the micelle sizes of CTAB and CPB with hydroperoxides, but leads to a decrease in micelle size in the case of ACh–ROOH.

On the one hand, a “bridge” between the chemistry of such microheterogeneous systems and neurochemistry is readily apparent, because in nervous tissue acetylcholine (ACh) is also conveyed in the form of microheterogeneous entities - synaptosomes. Although synaptosomes are not fully equivalent to the micelles used in model microheterogeneous systems, they nevertheless represent prototypical objects for model descriptions of ACh-signal transmission^123-143.

On the other hand, emphasizing the role of cholesterol naturally connects this line of inquiry with nutraceutical science and foodomics, while cholinergic neuromuscular synapses, in this context, additionally link ACh-containing microheterogeneous systems to myology. One may also raise the question of whether electrophysiological and magnetobiological phenomena in ACh neurotransmission are related to the structure of microheterogeneous “neuromimetic” micellar systems that carry those “quanta” of the ACh neurotransmitter and that can likewise be transmitted-at least in model systems. Thus, Kasaikina and Pisarenko report the following:

·                  Oxygen and an external magnetic field were found to exert a retarding effect on the rate of radical initiation during hydroperoxide decomposition in catalytic nanoreactors. Mixed reverse micelles formed by a cationic surfactant and a hydroperoxide, {mLOOH...n surfactant}, served as the nanoreactors.

·                  Similar effects of oxygen and an external magnetic field (60-150 mT) on the rate of radical initiation were observed for the catalytic radical decomposition of a hydroperoxide in the presence of acetylcholine.

·                  Notably, the retarding effect of the magnetic field decreased in the presence of paramagnetic species—oxygen and relatively stable radicals.

Similarly, Kasaikina, et al. state¹⁴⁴:

·                  It was established that acetylcholine, a key neurotransmitter that plays a substantial role in neuromuscular and cognitive activity in living organisms, in organic media catalyzes the radical decomposition of hydroperoxides in a manner analogous to cationic surfactants; under these conditions, the radical yield decreases in a magnetic field and in the presence of oxygen.

Accordingly, one can substantiate, on the one hand, the need to include acetylcholine and other neurotransmitters in the discussion as antioxidants and, on the other hand, the need to consider thiols.

4. History of Gas Chromatography and GC–MS of Thiols

To begin, it is useful to consider-using a concrete example-methodological approaches to the additive separation and practical identification of specific redox factors and antioxidants that are applicable (or relevant) to physiology and medicine. In view of the above, thiols appear to be a reasonable starting point. Given the reproducibility of a range of analytical methods for thiols, similarly to other redox agents and antioxidants, it was decided to implement this approach on the basis of gas chromatography.

The earliest studies on the gas chromatographic analysis of thiols-particularly on their separation from other components in complex mixtures-date to the early 1960s¹⁴⁵. For a long time, however, widespread adoption was constrained by the technical capabilities available at the time, which were insufficient for efficient analysis. The introduction in the 1980s of methods that simplified thiol analysis (including headspace gas chromatography¹⁴⁶) enabled a marked intensification of research in the 1990s. In particular, the emergence of affordable MS detectors and integrated GC-MS hardware–software platforms made it possible to develop experimental protocols that included not only chromatographic separation but also direct identification, including multiparametric identification using multiple detectors, in native and synthetic matrices containing thiols^147-149. It also became feasible to compare data obtained by methods using different phases-for example, GC–MS and HPLC.

By the mid-2000s, the predominance of GC–MS over “stand-alone” GC in thiol analysis had become established and this trend began to extend to catalytically generating systems employing various agents, including photocatalysts and others¹⁵⁰. Subsequent microminiaturization enabled analyses not only on conventional columns but also on capillary or needle-type columns, including chromatographic–mass-spectrometric formats such as NTD-GC–MS¹⁵¹.

In the mid-2010s, applications of tandem GC–MS to these tasks became increasingly prominent^152,153. Improved mass-spectrometer resolving power-including that of designs integrally coupled to GC–MS systems and used in MS/MS-enabled precise and reproducible isotope analysis¹⁵⁴. In addition, the advent of field-deployable and mobile mass spectrometers made it possible to integrate gas chromatographic analysis with olfactometry (as an alternative to “electronic nose” technologies) for comparative odorological and flavor-chemical studies. During the same period, gas chromatographic methods that do not rely on mass-spectrometric detection also continued to develop, but substantially more slowly, as their capabilities have largely been exhausted. Nevertheless, notable advances include the chiral gas chromatographic separation of products of thiol-ene synthesis / “click chemistry”¹⁵⁵. To date, most applied studies involving natural raw materials are generally performed using conventional GC-MS, albeit with various methodological innovations at the stages of sample preparation and separation¹⁵⁶.

Using an “inhibitor method,” it has been established that the reduction of hydrogen peroxide by thiols in aqueous solutions is typically accompanied by radical formation. Specifically, the interaction of glutathione and the synthetic/semi-biosynthetic thiol N-acetylcysteine with hydrogen peroxide at \mathrmpH<7 generates thiyl and hydroxyl radicals¹⁵⁷. This, in particular, supports the use of luminescence methods and electron paramagnetic resonance in addition to mass spectrometry.

5. History of Gas Chromatography and GC–MS of N‑Acetylcysteine

As noted above, the interaction of the thiol N‑acetylcysteine (NAC) with hydrogen peroxide in the presence of glutathione is of particular interest. Accordingly, it is reasonable to consider next the methodological development of GC and GC–MS approaches for NAC determination.

In this context, the following can be noted. GC analysis of NAC has been performed at least since the late 1970s¹⁵⁸. By the early 1990s, these assays had largely transitioned to capillary GC formats¹⁵⁹, reflecting the general shift toward higher-efficiency separations and improved sensitivity.

In parallel, GC coupled with mass-spectrometric detection was introduced for NAC measurements, including applications in blood plasma and other biogenic, partially structured matrices¹⁶⁰. By the 2000s, GC-MS-based determination of NAC (and related sulfur-containing metabolites) had been incorporated into clinical laboratory diagnostic workflows in both the United States and the European Union, for example in routine urine analysis¹⁶¹. As a result, the core analytical tasks of identification and clinical interpretation based on mass spectrometry-also encompassing NAC quantification for pharmacokinetic and pharmacodynamic purposes-are now well supported by established clinical MS practice.

6. History of Gas Chromatography and GC-MS of Acetylcholine

The gas-phase determination of neurotransmitters is of considerable interest, as it aligns well with the conceptual framework of “gas biology” and lays the groundwork for qualitatively new directions such as gas neurochemistry and gas-phase biochemical neurophysiology. One of the best-known neurotransmitters of the parasympathetic nervous system is acetylcholine. Purely gas-chromatographic methods for acetylcholine determination have been known since the 1960s^162-164. As a rule, these studies employed pyrolytic gas chromatography^165-171. However, from the second half of the 1960s onward, combined gas chromatography/mass spectrometry approaches also began to be introduced^172-177, including methods capable of measuring acetylcholine at subpicomolar amounts-although this did not preclude the continued use in the 1970s and later of conventional gas^178,179 or gas-liquid^180,181 chromatography.

The integration of pyrolytic gas chromatography and mass spectrometry in the analysis of acetylcholine and other neurotransmitters took place in the mid-1970s^182-184 and reached conceptual maturity in the 1980s, with the emergence of pyrolytic chromatography with MS detection, achieving at least picomolar concentration levels and being integrated with mass fragmentography^185-188. In acetylcholine analysis, the era of pyrolytic chromatography ended in the 1990s for reasons related to the advent of more sensitive technologies¹⁸⁹.

By that time, mass-spectrometric analytics had already developed methods such as secondary-ion mass spectrometry for compounds of this type¹⁹⁰, surface-ionization mass spectrometry¹⁹¹, MALDI¹⁹² and liquid chromatography with mass-spectrometric detection-including tandem mass spectrometry¹⁹³ and micro- and semi-micro-HPLC inlet technologies¹⁹⁴-as well as fast-atom bombardment methods^195,196. In response to increased analytical requirements and improved sample-preparation strategies, GC-MS was combined with intracerebral microdialysis¹⁹⁷. In GC-MS, an approach based on the interpretation of electron-impact mass spectra became established^198,199. Nevertheless, a purely pyrolytic approach continued to be applied in the 1990s as well²⁰⁰.

7. Historical development of gas chromatography and GC–MS for catecholamines and their metabolites

Catecholamines are generally defined as physiologically active compounds-derivatives of pyrocatechol-that act as chemical messengers and regulatory molecules (mediators and neurohormones) in intercellular communication in animals and humans, including within the brain. As is well known, this class includes neurotransmitters such as adrenaline/epinephrine, noradrenaline/norepinephrine and dopamine.

The history of gas-chromatographic determination of catecholamines and their metabolites dates back to the 1960s-1970s and was, from the outset, closely associated with mass spectrometry^201-206. Studies on the GC determination of catecholamines in the absence of MS detection during the 1970s constitute a separate branch that did not shape the main direction of the field^207,208, a limitation that many authors attributed to the lack of optimal chromatographic columns. As an intermediate line of development, gas-liquid chromatography of these compounds also progressed during the 1970s^209,210. During the 1980s, the relative merits of gas versus liquid chromatography for catecholamine analysis continued to be debated²¹¹. However, from the early 1980s through the 2000s, advances in the GC analysis of catecholamines-irrespective of the detector employed-were largely driven by the introduction of capillary columns^212-214.

From the mid-1980s onward, GC-MS methodologies incorporating real-time tracking and monitoring of selected ions, including negative ions, were introduced for catecholamine analysis^215,216. With the development of thermodesorber technology and microwave-assisted derivatization, sample preparation and conversion of analytes into GC-compatible forms were simplified²¹⁷, which also had a favorable impact on GC–MS-based catecholamine assays.

In the 2010s, GC–MS and GC–MS/MS methods for catecholamines and their metabolites became widely adopted in laboratory and clinical practice, typically as routine analytical procedures accessible to mid-level laboratory personnel. At the same time, the accuracy of mass-spectrometric measurements increased with the introduction of new detector technologies, particularly high-resolution Orbitrap (“Makarov trap”) analyzers. Among many examples of GC–MS and GC–MS/MS applications to catecholamine analysis are the studies by Zoerner, et al. and Nguyen, et al.^218,219.

8. Historical development of gas chromatography and GC-MS for hydroperoxides

The history of the gas-chromatographic analysis of hydroperoxides, as well as their use in gas chromatography, apparently dates back to the 1970s^220,221. By the early 1980s, capillary columns were already being actively employed in this area²²² and by the end of that decade the field had joined the broader trend toward integrating gas chromatography with mass spectrometry²²³. Work along these lines continued through the 1980s²²⁴ and into the 1990s^225-227. During this period, attempts were made both to integrate and to compare GC–MS with GC using flame-ionization detection²²⁸, as well as to integrate and benchmark GC–MS (including ion-trap detection, GC-ITDMS) against high-performance liquid chromatography for these analytes²²⁹. The 1980s–1990s also saw the evaluation of a number of relatively “exotic” approaches in this analytical domain, including on-column injection²³⁰.

By around 2000, numerous specialized columns and kits optimized for hydroperoxide determination had been introduced and validated, enabling their reliable detection even without mass-spectrometric detection^231-233. This trend matured into an optimized, quantitative framework by the mid-2010s²³⁴ and was further supported by chemometric tools, offering a low-cost solution for routine, high-throughput laboratories where instrumentation may be limited to GC with an FID detector²³⁵. However, such approaches are not suitable for operation with a thermal conductivity detector because of the well-known limitations of that detector. In better-equipped settings operating under good laboratory practice (GLP), mass-spectrometric detection is generally considered preferable for hydroperoxide analysis, often in conjunction with cross-validation against other methods such as thin-layer chromatography (TLC)^236,237. At a minimum, widely available and technically straightforward MS instrumentation employing electron ionization is sufficient for these purposes²³⁸.

9. Historical development of gas chromatography and GC-MS for phosphatidylcholine

There are fewer publications on the gas-chromatographic analysis of phosphatidylcholine than proponents of classical GC might wish. Beginning in the 1970s with gas–liquid chromatography²³⁹, this line of work rapidly shifted its emphasis toward GC-MS, primarily targeting acetolysis products²⁴¹. Thereafter, methodological development progressed only modestly, broadly following the patterns outlined above for the other compound classes considered here. In the 2010s-somewhat later than for the other analytes discussed-GC-MS applications expanded to include “nontraditional” extraction techniques such as headspace solid-phase microextraction (HS-SPME)²⁴². A distinctive feature of the GC-related trajectory for phosphatidylcholine has been its integration with and comparison to, matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS)²⁴³.

10. History of the preparation of the present article

The present paper is based on several previously unpublished documents and, in some cases, on the corresponding transcripts of presentations delivered at bibliographic seminars:

·                  A bibliographic annotated list (used as a working outline) on chromatographic methods for a range of neurotransmitters (covering publications up to the 2010s), compiled and used by the second author during dissertation work, as well as earlier purely abstracting material-largely historical and science-historical in nature-on the development of gas chromatography of neurotransmitters up to the 1990s (prepared during the pre-graduation period while working with outdated instrumentation, under the supervision of a specialist in biogenic monoamines). The contribution of these sources to the present work is estimated at approximately 30%.

·                  A bibliographic annotated list on gas chromatography and potentiometry in antioxidant chemistry, prepared during an attempt to organize RD on position-sensitive redox-metric measurements and gasometric microscopy at the Institute of Chemical Physics of the Russian Academy of Sciences (2011-2012). This work was discontinued due to termination of the contract and the lack of staff positions in the Department of Dynamics of Chemical and Biological Processes. This source accounts for approximately 10% of the bibliography used here.

·                  A bibliographic annotated list on applications of gas chromatography in neurochemical research, compiled during the second author’s employment in the Laboratory of Neuronal Brain Structure, Department of Brain Research, Scientific Center of Neurology of the Russian Academy of Medical Sciences (2012-2013). Unfortunately, by the mid-2010s these research plans were disrupted: following the reform of the Russian Academy of Sciences, the Laboratory of Neuronal Brain Structure was soon dissolved and the remaining chromatographic equipment (partly purchased by the authors with personal funds) was disposed of. The contribution of this source is up to 20%.

·                  A bibliographic annotated list on neurochemical applications of GC–MS (maintained in several versions and updated annually from 2013 to 2016 during the second author’s work in a mass-spectrometry laboratory at the Institute of Energy Problems of Chemical Physics of the Russian Academy of Sciences), as well as a similar frequently updated outline for antioxidant-related studies. These lists often included other mass-spectrometric approaches discussed in a comparative context. The contribution of these sources to the present work is estimated at approximately 30%. Unfortunately, owing to the obsolescence of the VARIAN- and Finnigan MAT–based GC–MS instrumentation at the institute, these approaches were not implemented there in routine practice.

·                  An updated (relative to item 2) bibliographic annotated list on GC and GC–MS in studies of neurotransmitters, bio antioxidants and antibacterial drugs, compiled with active participation of all authors. This list was prepared in the early 2020s for the management of the Department of Dynamics of Chemical and Biological Processes of the Federal Research Center for Chemical Physics of the Russian Academy of Sciences (formerly the Institute of Chemical Physics, RAS) and for the Laboratory of Liquid-Phase Oxidation of the same center. However, due to reorganization processes and redistribution of laboratory space, this document ultimately became unused. The equipment preserved by the authors was subsequently disposed of during the takeover of the premises (room 164) and only partly moved to unsafe rooms in Building 1 of the center, where a ceiling collapse later occurred. In view of the accelerating degradation of the GC/GC–MS infrastructure and the associated laboratory facilities, the authors jointly decided to publish an abridged version of the review material in its current form (without converting the accumulated bibliographic groundwork into empirical GC or GC–MS articles corresponding to the substance-specific sections of the review). We do not anticipate that we will be able to continue work in this direction; therefore, lacking support from a number of colleagues, we are not attempting to upgrade this review note to a full-scale, high-impact review article (in which citing those colleagues would be appropriate). Instead, we present what can reasonably be published given the material and technical resources available (and unavailable) to us.

11. Perspectives and Challenges (Discussions with Students)

A practically important challenge in contemporary redox medicine is not merely to use antioxidants, but to reliably and reproducibly detect and quantify antioxidant compounds and the associated redox markers in real samples: natural matrices (plant raw materials, foods), pharmaceutical substances and precursors, as well as human biomaterials (tissues, blood, urine, saliva, exhaled breath condensate and others). In European and U.S. research agendas, this is directly linked to a shift from “descriptive redox biology” toward measurable redox medicine and precision medicine, where decisions are grounded in validated biomarkers, standardized preanalytical procedures and interlaboratory-comparable data. Without objective assessment of the redox status of biosystems (and its temporal dynamics), it is impossible to develop a constructive approach to what may be broadly termed redox pathology, redox etiology and redox prevention: one cannot properly evaluate the contribution of oxidative stress, compare patient cohorts, rationally select an intervention strategy (diet, nutraceuticals, pharmacological antioxidants) or monitor treatment effects.

Contemporary experience from clinical trials of antioxidants has shown that “universal” regimens often yield equivocal outcomes precisely because interventions are implemented without sufficient characterization of baseline redox profiles and without monitoring of target molecular changes. This underscores the pivotal role of analytical chemistry and analytical biochemistry technologies for antioxidants: they provide the measurement framework for formulating redox-medicine problems, comparable in importance to the role that standardized hormone panels have played in endocrinology and that lipid profiles and high-sensitivity troponin have played in cardiology.

It is therefore important to distinguish between methods that evaluate “overall activity” and those that identify specific molecules. A number of widely used approaches capture integral reducing-oxidizing capacity or a global response (e.g., potentiometric measurements of redox potential, certain assays of total antioxidant capacity). Such methods are useful for screening; however, they are generally nonselective with respect to composition and poorly resolve the contributions of individual redox couples, oxidation products, metal complexes and matrix effects. In a clinical and biological context, this means that what is measured is not the “set of chemical systems actually operating in a given environment,” but rather an aggregate signal that may be identical despite fundamentally different molecular causes.

The modern redox concept assumes that many antioxidant mechanisms operate in microheterogeneous and ultramicroheterogeneous environments: membranes, lipoproteins, mitochondria, peroxisomes, the endoplasmic reticulum, granules and microdomains differing in ionic strength, pH, dielectric permittivity and local metal availability. Biological tissue with its organelles and compartments is a particularly illustrative example. Consequently, additive (essentially “summative”) assessments and inferences about “overall redox efficacy” are insufficiently rigorous for redox medicine: they do not allow observations to be linked reliably to mechanism and, ultimately, to clinical decision-making.

A minimally appropriate analytical level is the separate quantitative determination of key redox components and markers (e.g., individual low-molecular-weight antioxidants, their oxidized/reduced forms, lipid peroxidation products, oxysterols, markers of carbonyl stress and the like). The most advanced level is position- and compartment-sensitive analysis-i.e., measurement performed precisely where the reaction process unfolds (within an organelle, in a membrane, in the extracellular space or in a specific cell type). This task already belongs to the domains of cytochemistry, spatially resolved biochemistry and ultrastructural approaches and it requires specialized sample preparation and imaging methods; it may therefore fall outside the scope of the present review.

12. Acknowledgements

The authors would like to thank their colleagues for proofreading the machine translation of this review.

13. Reference
1.                Kancheva VD, Kasaikina OT. Bio-antioxidants - a chemical base of their antioxidant activity and beneficial effect on human health. Curr Med Chem, 2013;20(37): 4784-805.
2.                Guseva DA, Prozorovskaia NN, Shironin AV, et al. [Antioxidant activity of vegetable oils with various omega-6/omega-3 fatty acids ratio]. Biomed Khim, 2016;56(3): 342-350.
3.                Baranova VS, Rusina IF, Guseva DA, et al. The antiradical activity of plant extracts and healthful preventive combinations of these extracts with the phospholipid
complex. Biomed Khim, 2012;58(6): 712-726.
4.                Ozhogina OA, Kasaikina OT. Beta-carotene as an interceptor of free radicals. Free Radic Biol Med, 1995;19(5): 575-581.
5.                Kasaikina OT, Kartasheva ZS, Lobanova TV, et al. Effect of the environment on beta-carotene reactivity toward oxygen and free radicals.
Membr Cell Biol, 1998;12(2): 213-222.
6.                Halliwell B. Reactive species and antioxidants. Redox biology is a fundamental theme of aerobic life. Plant physiology, 2006;141(2): 312
322.
7.                Circu ML, Aw TY. Redox biology of the intestine. Free radical research, 2011;45(11-12): 1245-1266.
8.                Flohé L. Looking back at the early stages of redox biology. Antioxidants, 2020;9(12): 1254.
9.                Feelisch M, Cortese-Krott MM, et al. Systems redox biology in health and disease. EXCLI journal, 2022;21: 623.
10.             Sies H. Oxidative stress: impact in redox biology and medicine. Archives of Medical and Biomedical Research, 2015;2(4): 146-150.
11.             Ali RAR, Walker DG. International Conference on Antioxidants and Diseases ICADD 2018 New Frontiers in Omics and Redox Medicine
18-19th July 2018 Pullman Kuala Lumpur City Centre Abstracts. Medicine and Health (Kuala Lumpur), 2018;13(2): 351.
12.             Mas-Bargues C, Borrás C, Viña J. Redox medicine in viral infections: focus on AIDS and COVID-19. Redox Experimental Medicine, 2022;2022(1): 168-178.
13.             Bellanti F, Vendemiale G, Serviddio G. Redox experimental medicine and liver regeneration. Redox Experimental Medicine, 2022;2022(1): 69-82.
14.             Bourgonje AR, Kloska D, Grochot-Przęczek A, et al. Personalized redox medicine in inflammatory bowel diseases: an emerging role for
HIF-1α and NRF2 as therapeutic targets. Redox Biology, 2023: 102603.
15.             Huang X, Moir RD, Tanzi RE, et al. Redox‐active metals, oxidative stress and Alzheimer's disease pathology. Annals of the New York
Academy of Sciences, 2004;1012(1): 153-163.
16.             Burgoyne JR, Mongue-Din H, Eaton P, et al. Redox signaling in cardiac physiology and pathology. Circulation research, 2012;111(8):
1091-1106.
17.             Li W, McIntyre TM, Silverstein RL. Ferric chloride-induced murine carotid arterial injury: A model of redox pathology. Redox
biology, 2013;1(1): 50-55.
18.             Frye RE, James SJ. Metabolic pathology of autism in relation to redox metabolism. Biomarkers in medicine, 2014;8(3): 321-330.
19.             Handy DE, Loscalzo J. Selenoproteins in Cardiovascular Redox Pathology. In: Hatfield, D., Schweizer, U., Tsuji, P., Gladyshev, V. (eds) Selenium. Springer, Cham, 2016: 463-474.
20.             Chen Y, Li J, Zhao Z. Redox control in acute lymphoblastic leukemia: from physiology to pathology and therapeutic opportunities. Cells, 2021;10(5): 1218.
21.             Aitken RJ, Curry BJ. Redox regulation of human sperm function: from the physiological control of sperm capacitation to the etiology of
infertility and DNA damage in the germ line. Antioxidants & redox signaling, 2011;14(3): 367-381.
22.             Da Costa JGF. Redox modulation by sod mimics in renal cancer: from etiology to progression (Doctoral dissertation, Universidad de
Alcalá), 2018.
23.             Bailey DM. Redox Regulation of Post-Prandial Vascular Endothelial Dysfunction: Prophylactic Benefits of High-Intensity Exercise. Journal
of the American College of Cardiology, 2010;55(3): 258-258.
24.             Silva LCG, Angrimani DSR, Regazzi FM, et al. Pulmonary changes and redox status after fractionalized dose of prophylactic surfactant
treatment in preterm neonatal lambs. Journal of Applied Animal Research, 2020;48(1): 220-227.
25.             Diplock AT. Antioxidant nutrients and disease prevention: an overview. The American journal of clinical nutrition, 1991;53(1): 189S-193S.
26.             Harman D. Role of antioxidant nutrients in aging: overview. Age, 1995;18(2): 51-62.
27.             Ji L. Oxidative stress during exercise: implication of antioxidant nutrients. Free Radical Biology and Medicine, 1995;18(6): 1079-1086.
28.             Packer L. Oxidants, antioxidant nutrients and the athlete. Journal of sports sciences, 1997;15(3): 353-363.
29.             Ruhe RC, McDonald RB. Use of antioxidant nutrients in the prevention and treatment of type 2 diabetes. Journal of the American College of Nutrition, 2001;20(5): 363-369.
30.             Fraga CG, Oteiza PI. Iron toxicity and antioxidant nutrients. Toxicology, 2002;180(1): 23-32.
31.             Askew EW. Work at high altitude and oxidative stress: antioxidant nutrients. Toxicology, 2002;180(2): 107-119.
32.             Quiles JL, Huertas JR, Battino M, et al. Antioxidant nutrients and adriamycin toxicity. Toxicology, 2002;180(1): 79-95.
33.             Hsu PC, Guo YL. Antioxidant nutrients and lead toxicity. Toxicology, 2002;180(1): 33-44.
34.             Gaetke LM, Chow CK. Copper toxicity, oxidative stress and antioxidant nutrients. Toxicology, 2003;189(1-2): 147-163.
35.             McDonough KH. Antioxidant nutrients and alcohol. Toxicology, 2003;189(1-2): 89-97.
36.             Heyland DK, Dhaliwal R, Suchner U, et al. Antioxidant nutrients: a systematic review of trace elements and vitamins in the critically ill patient. Intensive care medicine, 2005;31: 327-337.
37.             Granados-Principal S, Quiles JL, Ramirez-Tortosa CL, et al. New advances in molecular mechanisms and the prevention of adriamycin toxicity by antioxidant nutrients. Food and Chemical Toxicology, 2010;48(6); 1425-1438.
38.             Bagirov NA. Forecasting of complications after extracapsular extractions of a cataract with IOL implantation depending on antioxidant status of patients, 2004;(3): 64-69.
39.             Bocharova O, Bocharova M. Forecasting and evaluating antioxidant properties of fruit and vegetable, juices using polarization curves. Journal of Food Processing and Preservation, 2017;41(6): 13225.
40.             Huyut MT, Huyut Z. Forecasting of Oxidant/Antioxidant levels of COVID-19 patients by using Expert models with biomarkers used in the Diagnosis/Prognosis of COVID-19. International Immunopharmacology, 2021;100: 108127.
41.             Robards K, Dilli S. Analytical chemistry of synthetic food antioxidants. A review. Analyst, 1987;112(7): 933-943.
42.             Sawai Y, Moon JH. Analytical Approach to Clarify the Molecular Mechanisms of the Antioxidative and Radical-Scavenging Activities of Antioxidants in Tea Using. Journal of Agricultural and Food Chemistry, 2000;48(12): 6247-6253.
43.             Perrin C, Meyer L. Analytical and Physical Chemistry-Simultaneous Determination of Ascorbyl Palmitate and Nine Phenolic Antioxidants in Vegetable Oils and Edible Fats by HPLC. Journal of the American Oil Chemists' Society, 2003;80(2): 115-118.
44.             Budnikov GK, Ziyatdinova GK. Antioxidants as analytes in analytical chemistry. Journal of Analytical Chemistry, 2005;60: 600-613.
45.             Ziyatdinova GK, Budnikov HC. Spice antioxidants as objects of analytical chemistry. Journal of Analytical Chemistry, 2018;73: 946-965.
46.             Rumley AG, Paterson JR. Analytical aspects of antioxidants and free radical activity in clinical biochemistry. Annals of Clinical Biochemistry, 1998;35(2): 181-200.
47.      Abou-Elella FM, Farouk R, Ali M. Biochemistry & analytical biochemistry antioxidant and anticancer activities of different constituents extracted from Egyptian prickly pear cactus (Opuntia Ficus-Indica) peel. Biochemistry & Analytical Biochemistry, 2014;3(2): 2161-1009.
48.    Marmaro AP. Method Development of the Analytical and Biochemical Characterization of the Antioxidant Content of Honeybee Pollen (Doctoral dissertation, University of Scranton), 2017.
49.             Ivanova AV, Gerasimova EL, Gazizullina ER, et al. Potentiometric method for determination of kinetic characteristics of radical reactions in aqueous media. Russian Chemical Bulletin, 2017;66(8): 1428-1432.
50.             Braynina KZ, Ivanova AV, Sharafutdinova EK. News from universities. Evaluation of antioxidant activity of food products by using
potentiometry method. Food Technol, 2004;4: 73-75.
51.    Lee GJ, Lee SK, Kim JM, et al. Application feasibility of antioxidant activity evaluation using potentiometry in major depressive disorder. Electrochemistry, 2014;82(4): 264-266.
52.   Tessutti LS, Macedo DV, Kubota LT, et al. Measuring the antioxidant capacity of blood plasma using potentiometry. Analytical biochemistry, 2013;441(2), 109-114.
53.         Kazakov Y, Khodos M, Vidrevich M, et al. Potentiometry as a tool for monitoring of antioxidant activity and oxidative stress estimation in medicine. Critical Reviews in Analytical Chemistry, 2019;49(2): 150-159.
54.    Ivanova AV, Gerasimova EL, Gazizullina ER. An integrated approach to the investigation of antioxidant properties by potentiometry. Analytica chimica acta, 2020;1111: 83-91.
55.      Kasaikina OT, Krugovov DA, Mengele EA. Unusual antioxidant effects in multiphase and complex systems. European Journal of Lipid Science and Technology, 2017;119(6): e201600286.
56.        Pérez-Peiró M, Alvarado Miranda M, Martín-Ontiyuelo C, et al. Nitrosative and Oxidative Stress, Reduced Antioxidant Capacity and Fiber Type Switch in Iron-Deficient COPD Patients: Analysis of Muscle and Systemic Compartments. Nutrients, 2023;15(6): 1454.
57.        Yeum KJ, Aldini G, Krinsky NI, et al. Antioxidant nutrients in aqueous and lipid compartments of human plasma can remove free radicals generated by either hydrophilic or lipophilic radical generators. FASEB Journal, 2001;15(5): 954.
58.      Yeum KJ, Russell RM, Krinsky NI, et al. Biomarkers of antioxidant capacity in the hydrophilic and lipophilic compartments of human plasma. Archives of biochemistry and biophysics, 2004;430(1): 97-103.
59.    Aldini G, Yeum KJ, Russel RM, et al. A selective assay to measure antioxidant capacity in both the aqueous and lipid compartments of plasma. Nutritional Sciences, 2003;6(1): 12-19.
60.   Banu SK, Stanley JA, Sivakumar KK, et al. Editor’s highlight: exposure to CrVI during early pregnancy increases oxidative stress and disrupts the expression of antioxidant proteins in placental compartments. Toxicological Sciences, 2017;155(2): 497-511.
61.    Crapo JD, Chang LY, Oury T. Compartmentalization of radical reactions and antioxidants. Free Radical Biology and Medicine, 1993;15(5):536.
62.  Tan M, Lu J, Zhang A, et al. The distribution and cooperation of antioxidant (iso) enzymes and antioxidants in different subcellular compartments in maize leaves during water stress. Journal of Plant Growth Regulation, 2011;30: 255-271.
63.   Sundar D, Perianayaguy B, Reddy AR. Localization of antioxidant enzymes in the cellular compartments of sorghum leaves. Plant Growth Regulation, 2004;44: 157-163.
64.    Shafiq F, Iqbal M, Ashraf MA, et al. Foliar applied fullerol differentially improves salt tolerance in wheat through ion compartmentalization, osmotic adjustments and regulation of enzymatic antioxidants. Physiology and Molecular Biology of Plants, 2020;26: 475-487.
65.    Palma JM, Rodríguez-Ruiz M, Foyer CH, et al. Editorial: Subcellular compartmentalization of plant antioxidants and ROS generating
systems, volume II. Front Plant Sci., 2023;14: 1224289.
66.     Hinchen JD. Statistics in Analytical Chemistry. Journal of Chromatographic Science, 1967;5(12): 641-646.
67.   Frank IE, Pungor E, Veress GE. Statistical decision theory applied to analytical chemistry: Part 1. The statistical decision model and its relation to branches of mathematical statistics. Analytica Chimica Acta, 1981;133(3): 433-441.
68. Miller JC, Miller JN. Basic statistical methods for analytical chemistry. Part I. Statistics of repeated measurements. A review. Analyst, 1988;113(9): 1351-1356.
69.      Danzer K. Robust statistics in analytical chemistry. Fresenius' Zeitschrift für analytische Chemie, 1989;335: 869-875.
70.      Ziegel ER. Statistics and chemometrics for analytical chemistry. Technometrics, 2004;46(4): 498.
71.  Ellison SLR, Fearn T. Characterising the performance of qualitative analytical methods: Statistics and terminology. TrAC Trends in Analytical Chemistry, 2005;24(6): 468-476.
72.  Goncharov NV, Ukolov AI orlova TI, et al. Metabolomics: on the way to an integration of biochemistry, analytical chemistry and informatics. Biology Bulletin Reviews, 2015;5: 296-307.
73.    Zuo Y, Wang C, Zhan J. Separation, characterization and quantitation of benzoic and phenolic antioxidants in American cranberry fruit by GC− MS. Journal of agricultural and food chemistry, 2002;50(13): 3789-3794.
74.  Guo L, Xie MY, Yan AP, et al. Simultaneous determination of five synthetic antioxidants in edible vegetable oil by GC-MS. Analytical and bioanalytical chemistry, 2006;386(6): 1881-1887.
75.   Guo L, Xie MY, Yan AP, et al. Simultaneous Determination of Three Antioxidants in Edible Vegetation Oil by GC-MS. Journal of Analytical Science, 2007;23(2): 169.
76.        Shin HS. GC-MS determination of antioxidants in ground water contaminated with JP-8. Chromatographia, 2007;66(11): 893-897.
77.        Tsai TF, Lee MR. Determination of antioxidants and preservatives in cosmetics by SPME combined with GC-MS. Chromatographia, 2008;67(5): 425-431.
78.      Li C, Ju F, Li D. Simultaneous testing 10 preservatives and antioxidants in wine by GC-MS. China Brewing, 2009;6: 149-152.
79.      Zafra-Gómez A, Luzón-Toro B, Jiménez-Diaz I, et al. Quantification of phenolic antioxidants in rat cerebrospinal fluid by GC-MS after oral administration of
compounds. Journal of pharmaceutical and biomedical analysis, 2010;53(1): 103-108.
80.     Alin J, Hakkarainen M. Microwave heating causes rapid degradation of antioxidants in polypropylene packaging, leading to greatly increased specific migration to food simulants as shown by ESI-MS and GC-MS. Journal of agricultural and food chemistry, 2011;59(10): 5418-5427.
81.     Shuangshuang TANG. Simultaneous determination of antioxidants and preservatives in meatproducts by GC-MS. Meat Research, 2013;27(2): 18-20.
82.   Ahmad M, Baba WN, Gani A, et al. Effect of extraction time on antioxidants and bioactive volatile components of green tea (Camellia sinensis), using GC/MS. Cogent Food & Agriculture, 2015;1(1); 1106387.
83.    Nasr A, Saleem Khan T, Zhu GP. Phenolic compounds and antioxidants from Eucalyptus camaldulensis as affected by some extraction conditions, a preparative
optimization for GC-MS analysis. Preparative biochemistry & biotechnology, 2019;49(5): 464-476.
84. Viet TD, Xuan TD, Van TM, et al. Comprehensive Fractionation of Antioxidants and GC-MS and ESI-MS Fingerprints of Celastrus hindsii Leaves. Medicines, 2019;6(2): 64.
85.   Svečnjak L, Marijanović Z, Okińczyc P, et al. Mediterranean Propolis from the Adriatic Sea Islands as a Source of Natural Antioxidants: Comprehensive Chemical
Biodiversity Determined by GC-MS, FTIR-ATR, UHPLC-DAD-QqTOF-MS, DPPH and FRAP Assay. Antioxidants, 2020;9(4): 337.
86.   Frauscher M, Agocs A, Besser C, et al. Time-Resolved Quantification of Phenolic Antioxidants and Oxidation Products in a Model Fuel by GC-EI-MS/MS. Energy & Fuels, 2020;34(3): 2674-2682.
87.    Gupta MK, Anand A, Asati A, et al. Quantitative determination of phenolic antioxidants in fruit juices by GC-MS/MS using automated injector port silylation after
QuEChERS extraction. Microchemical Journal, 2021;160: 105705.
88.   Luong J, Gras R, Cortes HJ, et al. Multidimensional GC using planar microfluidic devices for the characterization of phenolic antioxidants in fuels. Journal of separation science, 2013;36(17): 2738-2745.
89.    Keene KA, Ruddy RM, Fhaner MJ. Investigating the relationship between antioxidants and fatty acid degradation using a combination approach of GC-FID and square-wave voltammetry. ACS omega, 2019;4(1): 983-991.
90.    Jeney E. Problems of dialectic determinism in biology and medicine. Orvosi Hetilap, 1962;103: 433-437.
91.    Bellu E. The Dialectical Significance of Chemistry in the Works of Fr. Engels. Revue Roumaine Des Sciences Sociales, Serie Philosophie Et Logique, 1973;17(2): 163-169.
92.    Budreiko NA. The Formation of a Dialectical-Materialist Outlook in the Study of Chemistry (I). Soviet Education, 1974;16(9-10): 31-47.
93.   Budreiko NA. The Formation of a Dialectical-Materialist Outlook in the Study of Chemistry (II). Soviet Education, 1974;16(9-10): 48-70.
94.     Goldstein DS. On the dialectic between molecular biology and integrative physiology: Toward a new medical science. Perspectives in biology and medicine, 1997;40(4): 505-515.
95.    Neves RFD, Carneiro-Leão AMDA, Ferreira HS. The interaction of Kelly's experience circle with the hermeneutic-dialectic circle for the construction of concepts in Biology. Ciência & Educação (Bauru), 2012;18: 335-352.
96.     Pechenkin A. The dialectics of the correlation of chemistry. Epistemology & Philosophy of Science, 2014;40(2): 157-173.
97.     Imyanitov NS. Dialectics and synergetics in chemistry. Periodic Table and oscillating reactions. Foundations of Chemistry, 2016;18(1): 2156.
98.   Núñez IB, Silva SDRD. The dialectic systemic approach and the organization of Chemistry contents: didactic-philosophical reflections. Educação e Filosofia, 2019;33(67): 275-305.
99.        Zhu T, Wang B. Course Ideology and Politics in Fundamental Organic Chemistry Teaching: an Exploration Based on the Philosophy of
Dialectical Materialism. University Chemistry, 2023;38(8): 49-54.
100.     Straghan E, Sharma G, Goldfarb P, et al. Identification of pro-oxidant or antioxidant characteristics of proteins and enzymes in membranes; use of liposome entrapped proteins and other thiol-containing compounds. Biochemical Society Transactions, 1996;24(3): 375.
101.    Graham A, Wood JL. Induction of thiol recycling by protein kinase C: a potentially pro-oxidant pathway for low-density lipoprotein oxidation. Biochemical Society Transactions, 1996;24(3): 467.
102.     Lynch SM, Frei B. Physiological thiol compounds exert pro-and anti-oxidant effects, respectively, on iron-and copper-dependent oxidation of human low-density lipoprotein. Biochimica et Biophysica Acta (BBA)-Lipids and Lipid Metabolism, 1997;1345(2): 215-221.
103.    Iwata S, Hori T, Sato N, et al. Adult T cell leukemia (ATL)-derived factor/human thioredoxin prevents apoptosis of lymphoid cells induced by L-cystine and glutathione depletion: possible involvement of thiol-mediated redox regulation in apoptosis caused by pro-oxidantstate. Journal of immunology, 1997;158(7): 3108 3117.
104.    Kim SH, Han SI, Oh SY, et al. Activation of heat shock factor 1 by pyrrolidine dithiocarbamate is mediated by its activities as pro-oxidant and thiol modulator. Biochemical and Biophysical Research Communications, 2001;281(2): 367-372.
105.   Leroy P. Anti-and pro-oxidant aspects of thiols; a physico-chemical, biochemical and cellular point-of-view. Acta Biochimica Polonica, 2003;50(1).
106.    Menon S, Venkataraman S, Goswami P. Thiol-antioxidant induced pro-oxidant signaling inhibits fibroblasts' progression from G1 to S: Regulatory role of Mn-superoxide dismutase (MnSOD) and cyclin D1. Free Radical Biology and Medicine, 2005;39: 146.
107.      Fujisawa S, Kadoma Y. Anti-and pro-oxidant effects of oxidized quercetin, curcumin or curcumin-related compounds with thiols or ascorbate as measured by the induction period method. in vivo, 2006;20(1): 39-44.
108.      Zinatullina KM, Kasaikina OT, Kuzmin VA, et al. Pro- and antioxidant characteristics of natural thiols. Russian Chemical Bulletin, 2018;67(4): 726-730.
109.      Valent I, Bednárová L, Schreiber I, et al. Reaction of N-Acetylcysteine with Cu2+: Appearance of Intermediates with High Free Radical Scavenging Activity: Implications for Anti-/Pro-Oxidant Properties of Thiols. International Journal of Molecular Sciences, 2022;23(11): 6199.
110.      Zinatullina KM, Kasaikina OT, Khrameeva NP, et al. Kinetic characteristics of the reaction of natural thiols with peroxyl radicals and hydrogen peroxide. Russian Chemical Bulletin, 2017;66(7): 1300-1303.
111.          Zinatullina KM, Kasaikina OT, Khrameeva NP, et al. Kinetic characteristics of the reaction of resveratrol with peroxyl radicals and natural thiols in aqueous medium Russian Chemical Bulletin, 2017;66(11): 2145-2151.
112.          Lissi E, Rubio MA. O2 (3Σ) and O2 (1Δ) processes in microheterogenous systems. Pure and applied chemistry, 1990;62(8): 1503-1510.
113.          Oliveira DM, Lala APV, Nunes SMT, et al. Singlet oxygen quantum yiedls of chlorin'E IND. 6'in homogeneous and microheterogenous
solutions. European Journal of Pharmaceutical Sciences, 2001;13: 159.
114.     Huang YP, Luo GF, Luo YJ, et al. The influence of spatial structures of mimetic peroxidases and medium microheterogenous for enzyme catalytic reaction. Chin J Anal Chem, 2005;33(5), 599-604.
115.          Bohström Z. Organic Synthesis in Microheterogenous Media. Chalmers University of Technology, 2012.
116.          Chakraborty M. Physicochemical investigations on microheterogenous systems with special reference to spectroscopic studies (Doctoral dissertation, University of North Bengal), 2013.
117.        Moreiraa LM, Lyonb JP. Ionic and non-ionic surfactants: Micelles, reverse micelles and micro heterogenous systems, 2022.
118.     Potapova NV, Krugovov DA, Kasaikina OT. Effect of some membrane lipids on radical generation in the system acetylcholine hydroperoxide. Bulgarian Chemical Communications, 2018;50: 275-279.
119.          Kasaikina OT. Mutual influence of lipid-antioxidant-surfactant in microheterogeneous systems. Bulgarian Chemical Communications, 2018;50: 254-259.
120.          Kasaikina OT, Potapova NV, Krugovov DA, et al. The influence of cholesterol on the generation of radicals in mixed reverse micelles of cationic surfactants with hydroperoxides. Russian Chemical Bulletin, 2018;67(11): 2141-2143.
121.        Zinatullina KM, Kasaikina OT, Khrameeva NP, et al. Interaction of natural thiols and catecholamines with reactive oxygen species. Bulgarian Chemical Communications, 2018;50: 25-29.
122.          Kasaikina OT, Pisarenko LM. Magnetic effects in hydroperoxide decomposition in mixed micelles with cationic surfactants. Russian
Chemical Bulletin, 2015;64(10): 2319-2324.
123.    Marchbanks RM. Exchangeability of radioactive acetylcholine with the bound acetylcholine of synaptosomes and synaptic vesicles. Biochemical Journal, 1968;106(1): 87-95.
124.     Booth RFG, Harvey SAK, Clark JB. Effects of in vivo hypoxia on acetylcholine synthesis by rat brain synaptosomes. Journal of Neurochemistry, 1983;40(1): 106-110.
125.          Gundersen Jr CB, Howard BD. The effects of botulinum toxin on acetylcholine metabolism in mouse brain slices and synaptosomes. Journal of Neurochemistry, 1978;31(4): 1005-1013.
126.          Roskoski Jr R. Acceleration of choline uptake after depolarization‐induced acetylcholine release in rat cortical synaptosomes. Journal of Neurochemistry, 1978;30(6): 1357-1361.
127.          Jope RS, Weiler MH, Jenden DJ. Regulation of acetylcholine synthesis: control of choline transport and acetylation in synaptosomes. Journal of neurochemistry, 1978;30(5): 949-954.
128.          Ksiezak HJ, Gibson GE. Oxygen dependence of glucose and acetylcholine metabolism in slices and synaptosomes from rat brain. Journal of Neurochemistry, 1981;37(2): 305-314.
129.          Weiler MH, Gundersen CB, Jenden DJ. Choline uptake and acetylcholine synthesis in synaptosomes: investigations using two different labeled variants of choline. Journal of neurochemistry, 1981;36(5): 1802-1812.
130.          Morel N, Meunier FM. Simultaneous release of acetylcholine and ATP from stimulated cholinergic synaptosomes. Journal of neurochemistry, 1981;36(5): 1766-1773.
131.          Jope RS. Acetylcholine turnover and compartmentation in rat brain synaptosomes. Journal of neurochemistry, 1981;36(5): 1712-1721.
132.          Israël M, Manaranche R, Morel N, et al. Redistribution of intramembrane particles related to acetylcholine release by cholinergic synaptosomes. Journal of Ultrastructure Research, 1981;75(2): 162-178.
133.       Israël M, Meunier FM, Morel N, et al. Calcium‐induced desensitization of acetylcholine release from synaptosomes or proteoliposomes equipped with mediatophore, a presynaptic membrane protein. Journal of neurochemistry, 1987;49(3): 975-982.
134.          Breer H, Knipper M. Characterization of acetylcholine release from insect synaptosomes. Insect biochemistry, 1984;14(3): 337-344.
135.          Adam-Vizi V, Ligeti E. Release of acetylcholine from rat brain synaptosomes by various agents in the absence of external calcium ions. The Journal of Physiology, 1984;353(1): 505-521.
136.          Meyer EM, Crews FT, Otero DH, et al. Aging decreases the sensitivity of rat cortical synaptosomes to calcium ionophore‐induced acetylcholine release. Journal of neurochemistry, 1986;47(4): 1244-1246.
137.          Boksa P, Mykita S, Collier B. Arachidonic acid inhibits choline uptake and depletes acetylcholine content in rat cerebral cortical synaptosomes. Journal of neurochemistry, 1988;50(4): 1309-1318.
138.          Satoh E, Nakazato Y. On the mechanism of ouabain‐induced release of acetylcholine from synaptosomes. Journal of neurochemistry, 1992;58(3): 1038-1044.
139.          Kirkpatrick KA, Richardson PJ. Adenosine receptor‐mediated modulation of acetylcholine release from rat striatal synaptosomes. British journal of pharmacology, 1993;110(3): 949-954.
140.   Ni Z, Smogorzewski M, Massry SG. Derangements in acetylcholine metabolism in brain synaptosomes in chronic renal failure. Kidney international, 1993;44(3): 630-637.
141.          Arribas M, Blasi J, Lazarovici P, et al. Calcium‐Dependent and‐Independent Acetylcholine Release from Electric Organ Synaptosomes by Pardaxin: Evidence of a Biphasic Action of an Excitatory Neurotoxin. Journal of neurochemistry, 1993;60(2): 552-558.
142.          Gifford AN, Bruneus M, Gatley SJ, et al. Cannabinoid receptor‐mediated inhibition of acetylcholine release from hippocampal and cortical synaptosomes. British journal of pharmacology, 2000;131(3): 645-650.
143.          Hornick A, Lieb A, Vo NP, et al. The coumarin scopoletin potentiates acetylcholine release from synaptosomes, amplifies hippocampal long-term potentiation and ameliorates anticholinergic-and age-impaired memory. Neuroscience, 2011;197: 280-292.
144.          Kasaikina OT, Potapova NV, Krugovov DA, et al. Catalysis of radical reactions in mixed micelles of surfactants with hydroperoxides. Kinetics and Catalysis, 2017;58(5):556-562.
145.          Farrugia VJ, Jarreau CL. Separation of Isopropyl Alcohol from Aliphatic Sulfides and Thiols by Gas Chromatography. Analytical Chemistry, 1962;34(2): 271-273.
146.       Zygmunt B, Przyjazny A. Application of headspace gas chromatography for the investigation of kinetics of oxidation of thiols by dimethyl sulphoxide in aqueous medium. Journal of Chromatography A, 1984;294: 117-125.
147.          Wroński M. Determination of volatile thiols by gas chromatography using separation astributyltin mercaptides. Journal of Chromatography A, 1991;555(1-2): 306-310.
148.          Kirichenko VE, Osipova OA, Pashkevich KI. Gas chromatography-mass spectrometry of perfluoroacyl derivatives of alkane thiols. Journal of Analytical Chemistry, 1996;51(11): 1061-1063.
149.          Tsikas D, Sandmann J, Rossa S, et al. Investigations of S-Transnitrosylation Reactions between Low-and High-Molecular-WeightS-Nitroso Compounds
and Their Thiols by High-Performance Liquid Chromatography and Gas Chromatography–Mass Spectrometry. Analytical biochemistry, 1999;270(2): 231-241.
150.          Courtney S, Voegel PD. GC/MS analysis of disulfides produced by aerobic oxidation of thiol mixtures using phthalocyanine and pyridinoporphyrazine catalysts. Abstracts of Papers of the American Chemical Society, 2005;230: 790.
151.          Warren JM, Parkinson DR, Pawliszyn J. Assessment of thiol compounds from garlic by automated headspace derivatized in-needle-NTD-GC-MS and derivatized in-fiber-SPME-GC-MS. Journal of agricultural and food chemistry, 2013;61(3): 492-500.
152.          Thibon C, Pons A, Mouakka N, et al. Comparison of electron and chemical ionization modes for the quantification of thiols and oxidative compounds in white wines by gas chromatography–tandem mass spectrometry. Journal of Chromatography A, 2015;1415: 123-133.
153.          Coetzee C, Schulze A, Mokwena L, et al. Investigation of thiol levels in young commercial South African Sauvignon Blanc and Chenin Blanc wines using propiolate derivatization and GC-MS/MS. South African Journal of Enology and Viticulture, 2018;39(2): 180-184.
154.          Pavez C, Agosin E, Steinhaus M. Odorant screening and quantitation of thiols in Carmenere red wine by gas chromatography-olfactometry and stable isotope dilution assays. Journal of agricultural and food chemistry, 2016;64(17): 3417-3421.
155.          Cui YY, Yang CX, Yan XP. Thiol-yne click post-modification for the synthesis of chiral microporous organic networks for chiral gas chromatography. ACS applied materials & interfaces, 2020;12(4): 4954-4961.
156.          Wenqing ZHANG, Naixin WANG, Wei WANG, et al. Analysis of Thiols in Naphtha With Michael Addition Derivatization Followed by Gas Chromatography-
Mass Spectrometry. Acta Petrolei Sinica (Petroleum Processing Section), 2021;37(1).
157.          Zinatullina KM, Kasaikina OT, Motyakin MV, et al. Specific features of radical generation in the reaction of thiols with hydrogen peroxide. Russ Chem Bull 2020;69: 1865-1868.
158.          Hannested U, Sörbo B. Determination of 3-mercaptolactate, mercaptoacetate and N-acetylcysteine in urine by gas chromatography. Clinica Chimica
Acta, 1979;95(2): 189-200.
159.     Takahashi S, Matsubara K, Hasegawa M, et al. Detection and measurement of S-benzyl-N-acetylcysteine in urine of toluene sniffers using capillary gas chromatography. Archives of toxicology, 1993;67(9): 647-650.
160.     Longo A, Di Toro M, Galimberti C, et al. Determination of N-acetylcysteine in human plasma by gas chromatography-mass spectrometry. Journal of Chromatography B: Biomedical Sciences and Applications, 1991;562(1-2): 639-645.
161.   Gopaul SV, Farrell K, Abbott FS. Gas chromatography/negative ion chemical ionization mass spectrometry and liquid chromatography/electrospray ionization tandem mass spectrometry quantitative profiling of N‐acetylcysteine conjugates of valproic acid in urine: application in drug metabolism studies in humans. Journal of mass spectrometry, 2000;35(6): 698-704.
162.          Stavinoha WB, Ryan LC, Treat EL. Estimation of acetylcholine by gas chromatography. Life Sciences, 1964;3(7): 689-693.
163.          Stavinoha WB, Ryan LC. Estimation of the acetylcholine content of rat brain by gas chromatography. Journal of Pharmacology and Experimental
Therapeutics, 1965;150(2): 231-235.
164.   Szilagyi PIA, Schmidt DE, Green JP. Microanalytical determination of acetylcholine, other choline esters and choline by pyrolysis-gas chromatography. Analytical chemistry, 1968;40(13): 2009-2013.
165.  Schmidt DE, Szilagyi PI, Alkon DL, et al. Acetylcholine: Release from neural tissue and identification by pyrolysis-gas chromatography. Science, 1969;165(3900): 1370-1371.
166.       Schmidt DE, Szilagyi PIA, Alkon DL, et al. A method for measuring nanogram quantities of acetylcholine by pyrolysis-gas chromatography: the demonstration of acetylcholine in effluents from the rat phrenic nerve-diaphragm preparation. Journal of Pharmacology and Experimental Therapeutics, 1970;174(2): 337-345.
167.          Green JP, Alkon DL, Schmidt DE, et al. Confirmation of acetylcholine in perfusates of the stimulated vagus nerve by pyrolysis gas chromatography. Life
Sciences, 1970;9(13): 741-745.
168.          Szilagyi PIA, Green JP, Brown OM, et al. The measurement of nanogram amounts of acetylcholine in tissues by pyrolysis gas chromatography 1. Journal
of neurochemistry, 1972;19(11): 2555-2566.
169.          Stavinoha WB, Weintraub ST. Estimation of choline and acetylcholine in tissue by pyrolysis gas chromatography. Analytical chemistry, 1974;46(6): 757
760.
170.          Schmidt DE, Speth RC. Simultaneous analysis of choline and acetylcholine levels in rat brain by pyrolysis gas chromatography. Analytical
biochemistry, 1975;67(1): 353-357.
171.          Maruyama Y, Kusaka M, Mori J, et al. Simple method for the determination of choline and acetylcholine by pyrolysis gas chromatography. Journal of
Chromatography B: Biomedical Sciences and Applications, 1979;164(2): 121-127.
172.          Hammar CG, Hanin I, Holmstedt B, et al. Identification of Acetylcholine in Fresh Rat Brain by Combined Gas Chromatography–Mass
Spectrometry. Nature, 1968;220(5170): 915-917.
173.          Jenden DJ, Roch M, Booth RA. Simultaneous measurement of endogenous and deuterium-labeled tracer variants of choline and acetylcholine in subpicomole quantities by gas chromatography/mass spectrometry. Analytical biochemistry, 1973;55(2): 438-448.
174.          Jenden DJ. The use of gas chromatography-mass spectrometry to measure tissue levels and turnover of acetylcholine. Advances in biochemical
psychopharmacology, 1973;7: 69-81.
175.          Jenden DJ, Choi L, Silverman RW, et al. (1974). Acetylcholine turnover estimation in brain by gas chromatography/mass spectrometry. Life
sciences, 14(1), 55-63.
176.          Hanin I, Schuberth J. Labelling of acetylcholine in the brain of mice fed on a diet containing deuterium labelled choline: studies utilizing gas
chromatography-mass spectrometry. Journal of neurochemistry, 1974;23(4): 819-824.
177.          Haug P, Suzuki M, Moritz J, et al. Changes in acetylcholine in caudate nucleus tissue isolated in situ detected by gas chromatography mass spectrometry
selected ion monitoring. Biomedical mass spectrometry, 1980;7(11-12): 533-536.
178.          Jenden DJ, Booth RA, Roch M. Simultaneous microestimation of choline and acetylcholine by gas chromatography. Analytical chemistry, 1972;44(11):
1879-1881.
179.          Tretyn A, Bobkiewicz W, Tretyn M, et al. The identification of acetylcholine and choline in oat seedlings by gas chromatography and nuclear magnetic
resonance (NMR). Acta Societatis Botanicorum Poloniae, 1987;56(3): 499-511.
180.          Chang MH. Quantitation of Acetylcholine in Insects by Gas Liquid Chromatography (Doctoral dissertation, University of Georgia), 1974;.
181.          Davies TJ, Hayward NJ. Volatile products from acetylcholine as markers in the rapid urine test using head-space gas-liquid chromatography. Journal of
Chromatography B: Biomedical Sciences and Applications, 1984;307: 11-21.
182.          Polak RL, Molenaar PC. Pitfalls in determination of acetylcholine from brain by pyrolysis gas chromatography/mass spectrometry. Journal of
neurochemistry, 1974;23(6): 1295.
183.          Fidone, S. J., Weintraub ST, Stavinoha WB. Acetylcholine content of normal and denervated cat carotid bodies measured by pyrolysis gas
chromatography/mass fragmentometry. Journal of neurochemistry, 1976;26(5): 1047-1049.
184.          Bishop MR, Sastry BR, Stavinoha WB. Identification of acetylcholine and propionylcholine in bull spermatozoa by integrate pyrolysis, gas chromatography
and mass spectrometry. Biochimica et Biophysica Acta (BBA)-General Subjects, 1977;500(2): 440-444.
185.          Khandelwal JK, Szilagyi PI, Barker LA, et al. Simultaneous measurement of acetylcholine and choline in brain by pyrolysis-gas chromatography-mass
spectrometry. European journal of pharmacology, 1981;76(2-3): 145-156.
186.          Boshart GE. Determination of acetylcholine and choline in biological materials using ion pair-high performance liquid chromatography and pyrolysis-gas
chromatography-mass fragmentography (Doctoral dissertation, ETH Zurich), 1981.
187.          Hasegawa Y, Kunihara M, Maruyama Y. Determination of picomole amounts of choline and acetylcholine in blood by gas chromatography-mass
spectrometry equipped with a newly improved pyrolyzer. Journal of Chromatography A, 1982;239: 335-342.
188.          Mori A, Watanabe Y, Yokoi I. Analysis of acetylcholine utilizing pyrolysis gas chromatography-mass spectrometry. Japanese Journal of
Pharmacology, 1986;40: 55-56.
189.          Terry Jr AV, Silks III LA, Dunlap RB, et al. Synthesis of novel selenium-containing choline and acetylcholine analogues and their quantitation using a pyrolysis-gas chromatography-mass spectrometry assay. Journal of Chromatography A, 1991;585(1): 101-109.
190.          Ohashi M, Lino T, Takahashi T, et al. Cluster ions in the secondary ion mass spectrometry of choline and acetylcholine halides. Organic mass spectrometry, 1990;25(2): 109-114.
191.          Rasulev UK, Nazarov ÉG, Nosirov VN, et al. Surface-ionization mass spectrometry of acetylcholine halides. Chemistry of natural compounds, 1998;34(1):
52-55.
192.          Kasheverov I, Utkin Y, Weise C, et al. Reverse-phase chromatography isolation and MALDI mass spectrometry of the acetylcholine receptor
subunits. Protein expression and purification, 1998;12(2): 226-232.
193.          Schroeder W, Meyer HE, Covey T, et al. Identification of Phosphorylation Sites in the Nicotinic Acetylcholine Receptor by Edman Degradation and Mass
Spectroscopy LC/MS and LC/MS/MS. In Cellular Regulation by Protein Phosphorylation 1991: 79-84.
194.          Acevedo LD, Xu Y, Zhang X, et al. Quantification of Acetylcholine in Cell Culture Systems by Semi‐micro–High‐Performance Liquid Chromatography and
Electrospray Ionization Mass Spectrometry. Journal of mass spectrometry, 1996;31(12): 1399-1402.
195.          Ishimaru H, Ikarashi Y, Maruyama Y. Use of high‐performance liquid chromatography continuous‐flow fast atom bombardment mass spectrometry for
simultaneous determination of choline and acetylcholine in rodent brain regions. Biological mass spectrometry, 1993;22(12): 681-686.
196.          Ishimaru H, Ikarashi Y, Maruyama Y, et al. Continuous-Flow Fast Atom Bombardment Mass Spectrometry of Acetylcholine: Interpretation of Mass Spectral
Fragmentation. Journal of the Mass Spectrometry Society of Japan, 1995;43(1): 19-26.
197.          Marien MR, Richard JW. Drug effects on the release of endogenous acetylcholine in vivo: Measurement by intracerebral dialysis and gas chromatography
mass spectrometry. Journal of neurochemistry, 1990;54(6): 2016-2023.
198.      Patterson TA, Kosh JW. Simultaneous quantitation of arecoline, acetylcholine and choline in tissue using gas chromatography/electron impact mass spectrometry. Biological mass spectrometry, 1992;21(6): 299-304.
199.          Patterson T, Kosh J. Quantitation of arecoline, acetylcholine and choline in brain-tissue using gas-chromatography electron-impact mass
spectrometry. FASEB Journal, 1992 ;6(4): 1014.
200.          Harris SE, Silks III LA, Dunlap RB, et al. Synthesis of novel tellurium containing analogues of choline and acetylcholine and their quantitation by pyrolysis
gas chromatography-mass spectrometry. Journal of Chromatography A, 1993;657(2): 395-404.
201.          Anggard E, Sedvall G. Gas chromatography of catecholamine metabolites using electron capture detection and mass spectrometry. Analytical
chemistry, 1969;41(10): 1250-1256.
202.          Brandenberger H, Schnyder D. Toxikologischer Spurennachweis von biologisch wirksamen Aminen (Amphetamine, Catecholamine, Halluzinogene) durch
Gas-Chromatographie mit massenspezifischer Detektion (GC-MD). Fresenius' Zeitschrift für analytische Chemie, 1972;261(4): 297-305.
203.          Cashaw JL, McMurtrey KD, Brown H, et al. Identification of catecholamine-derived alkaloids in mammals by gas chromatography and mass
spectrometry. Journal of Chromatography A, 1974;99: 567-573.
204.          Sjöquist B, Anggård E. Analysis of catecholamine metabolites by gas chromatography--mass spectrometry. Lakartidningen, 1976;73(8): 630-637.
205.          Sjöquist B. Analysis of catecholamine metabolites in tissues and body fluids: use of stable isotopes and gas chromatography-mass spectrometry (Doctoral
dissertation), 1975.
206.          Hattox SE, Murphy RC. Mass spectrometry and gas chromatography of trimethylsilyl derivatives of catecholamine related molecules. Biomedical mass
spectrometry, 1978;5(5): 338-345.
207.          Kishikawa H. Experimental and clinical studies on the catecholamine metabolism 1. Studies on the determination of catecholamines in tissues, serum,
urine and cerebrospinal fluid by gas chromatography (ECD). Okayama Igakkai Zasshi (Journal of Okayama Medical Association), 1975;87(5-6): 451-462.
208.          Nagai K, Iwaki Y, Hosoda N. Catecholamine determination in synaptosomes from rat-brain and bovine retina by gas-chromatography. Japanese Journal of
Pharmacology, 1977;27: 62.
209.          Goodwin BL, Ruthven CR, Sandler M, et al. Loss of catecholamine derivatives during gas-liquid chromatography. Clinica chimica acta; international journal
of clinical chemistry, 1973;44(2): 271-272.
210.          Boutagy J, Benedict C. Catecholamine Determination by Gas-Liquid Chromatography. Journal of chromatography, 1978;151(2): 263-264.
211.          Kleine T, Brause U, Tlatlik M. Determination of metabolites of catecholamine and indoleamine transmitters in human-urine by high-performance liquid
chromatography and gas-chromatography, comparison of both methods. Hoppe-Seylers Zeitschrift fur Physiologische Chemie, 1982;363(11): 1307-1308.
212.          Muskiet FA, Stratingh MC, Stob GJ, et al. Simultaneous determination of the four major catecholamine metabolites and estimation of a serotonin
metabolite in urine by capillary gas chromatography of their tert-butyldimethylsilyl derivatives. Clinical chemistry, 1981;27(2): 223-227.
213.          De Jong EBM, Horsten BPM, Goldschmidt HMJ. Determination of nine catecholamine metabolites and 5-hydroxyindolacetic acid in urine by capillary gas
chromatography. Journal of Chromatography A, 1983;279: 563-572.
214.      Grkovic S, Nikolic R, Dordevic M, et al. Urinary catecholamine metabolites: Capillary gas chromatography method and experience with 12 cases of neuroblastoma. Indian Journal of Clinical Biochemistry, 2005;20(2): 178-181.
215.          De Jong APJM, Kok RM, Cramers CA, et al. Determination of acidic catecholamine metabolites in plasma and cerebrospinal fluid using gas
chromatography-negative-ion mass spectrometry. Journal of Chromatography B: Biomedical Sciences and Applications, 1986;382: 19-30.
216.          Warsh JJ, Godse DD, Li PP. Quantitation of catecholamine metabolites by gas chromatography-mass spectrometry with selected ion monitoring. Methods
in enzymology, 1987;142: 571-582.
217.          Agatha G, Kauf E. GC analysis of steroids, fatty acids organic acids and catecholamine metabolites with microwave accelerated derivatization for the
diagnosis of metabolic disorders. Clinical laboratory, 1999;45(7-8): 387-397.
218.          Zoerner AA, Heusser K, Gutzki FM, et al. Unique pentafluorobenzylation and collision-induced dissociation for specific and accurate GC-MS/MS
quantification of the catecholamine metabolite 3, 4-dihydroxyphenylglycol (DHPG) in human urine. Journal of Chromatography B, 2011;879(17-18): 1444-1456.
219.          Nguyen DT, Cho IS, Kim JW, et al. Acidic metabolite profiling analysis of catecholamine and serotonin as O‐ethoxycarbonyl/tert‐butyldimethylsilyl
derivatives by gas chromatography–mass spectrometry. Biomedical Chromatography, 2013;27(2) : 216-221.
220.          Balducci S, Cesaroni C, Lorenzon L. Gas-chromatography analysis of cumene oxidation mixtures with preliminary reduction of cumene hydroperoxide by
triphenylphosphine. Chimica & L Industria, 1974;56(7): 516-517.
221.          Cairns GT, Diaz RR, Selby K, et al. Determination of organic peroxyacids and hydroperoxides by gas chromatography. Journal of Chromatography
A, 1975;103(2): 381-384.
222.          van Os CP, Rijke-Schilder GP, Kamerling JP, et al. Determination by capillary gas-liquid chromatography of the absolute configurations of unsaturated fatty
acid hydroperoxides formed by lipoxygenases. Biochimica et Biophysica Acta (BBA)-Lipids and Lipid Metabolism, 1980;620(2): 326-331.
223.          Selke E, Frankel EN, Neff WE. Thermal decomposition of methyl oleate hydroperoxides and identification of volatile components by gas chromatography
mass spectrometry. Lipids, 1978;13(7): 511-513.
224.          Frankel EN, Neff WE, Selke E. Analysis of autoxidized fats by gas chromatography-mass spectrometry: VII. Volatile thermal decomposition products of
pure hydroperoxides from autoxidized and photosensitized oxidized methyl oleate, linoleate and linolenate. Lipids, 1981;16(5): 279-285.
225.          Stephens R, Vankuijk F, Dratz E, et al. Long-term dietary vitamin-e depletion results in a 3-fold increase in hydroperoxides derived from docosahexaenoic
acid in the retina as determined by GC-MS. Investigative Ophthalmology & Visual Science, 1991;32(4): 703.
226.          Bächmann K, Hauptmann J, Polzer J, et al. Determination of organic alkyl-and 1-hydroxy hydroperoxides with chemiluminescence, fluorescence and
GC/MS. Fresenius' journal of analytical chemistry, 1992;342(10): 809-812.
227.          Turnipseed SB, Allentoff AJ, Thompson JA. Analysis of trimethylsilylperoxy derivatives of thermally labile hydroperoxides by gas chromatography-mass
spectrometry. Analytical biochemistry, 1993;213(2): 218-225.
228.          Polzer J, Bächmann K. Sensitive determination of alkyl hydroperoxides by high-resolution gas chromatography-mass spectrometry and high-resolution gas
chromatography with flame ionization detection. Journal of Chromatography A, 1993;653(2): 283-291.
229.          Bortolomeazzi R, Pizzale L, Vichi S, et al. Analysis of isomers of cholesteryl acetate hydroperoxides by HPLC and GC
ITDMS. Chromatographia, 1994;39(9-10): 577-580.
230.          Reddy KT, Cernansky NP, Cohen RS. GC/on-column injection technique to detect dodecyl hydroperoxides and their decomposition products. Analytical Chemistry, 1992;64(19): 2273-2276.
231.          Wierzchowski PT, Zatorski LW. Determination of cyclo C 6 and C 7 peroxides and hydroperoxides by gas chromatography. Chromatographia, 2000;51(1-2):
83-86.
232.          Lagarda MJ, Mañez JG, Manglano P, et al. Lipid hydroperoxides determination in milk‐based infant formulae by gas chromatography. European journal of
lipid science and technology, 2003;105(7): 339-345.
233.          Docherty KS, Kumboonlert K, Lee IJ, et al. Gas chromatography of trimethylsilyl derivatives of α-methoxyalkyl hydroperoxides formed in alkene-O3
reactions. Journal of Chromatography A, 2004;1029(1-2): 205-215.
234.          Zenkevich IG. Special features of gas chromatography determination of dibenzyl ether hydroperoxide impurity in benzyl alcohol. Russian Journal of
General Chemistry, 2016;86(9): 2016-2021.
235.          Leocata S, Frank S, Wang Y, et al. Quantification of hydroperoxides by gas chromatography‐flame ionization detection and predicted response
factors. Flavour and Fragrance Journal, 2016;31(4): 329-335.
236.          Kawai Y, Miyoshi M, Moon JH, et al. Detection of cholesteryl ester hydroperoxide isomers using gas chromatography-mass spectrometry combined with
thin-layer chromatography blotting. Analytical biochemistry, 2007;360(1): 130-137.
237.          Wiklund P, Karlsson C, Levin M. Determination of hydroperoxide content in complex hydrocarbon mixtures by gas chromatography/mass
spectrometry. Analytical Sciences, 2009;25(3): 431-436.
238.     Rudbäck J, Ramzy A, Karlberg AT, et al. Determination of allergenic hydroperoxides in essential oils using gas chromatography with electron ionizationmass spectrometry. Journal of separation science, 2014;37(8): 982-989.
239.          Harlow R, Mims L, Soodsma J. Analysis of fetal rabbit lung phosphatidylcholine by gas-liquid chromatography of diglyceride acetates. Journal of the
American Oil Chemists Society, 1974;51(7): A529.
240.          Hasegawa K, Suzuki T. Examination of acetolysis products of phosphatidylcholine by gas chromatography-mass spectrometry. Lipids, 1975;10(11): 667
672.
241.          Hasegawa K, Suzuki T. Examination of acetolysis products of phosphatidylcholine by gas chromatography-mass spectrometry. Lipids, 1975;10(11): 667
672.
242.          Zhou L, Zhao M, Khalil A, et al. Identification of volatiles from oxidised phosphatidylcholine molecular species using headspace solid-phase microextraction
(HS-SPME) and gas chromatography–mass spectrometry (GC-MS). Analytical and bioanalytical chemistry, 2013;405(28): 9125-9137.
243.          Vireque AA, Ferreira CR, Hatanaka RR, et al. Dataset on lipid profile of bovine oocytes exposed to Lα-phosphatidylcholine during in vitro maturation
investigated by MALDI mass spectrometry and gas chromatography-flame ionization detection. Data in brief, 2017;13: 480-486