If you have been reading about thiol and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-07-20. Numbers and descriptions here follow the published literature rather than marketing material.
In living systems, glutathione occurs in millimolar concentrations in many cell types, while extracellular levels are generally much lower. The liver holds a substantial share of the body's total pool, and the molecule participates in reduction, detoxification, and amino acid transport. It also serves as a cofactor for enzymes such as glutathione peroxidase and glutathione S-transferase. Because the cysteine residue supplies a reactive thiol, glutathione can donate electrons and become oxidized. Cells regenerate reduced glutathione through glutathione reductase using NADPH.
Commercial glutathione is produced by microbial fermentation or chemical synthesis, then purified. Reduced and oxidized grades are offered separately, with purity specifications often exceeding 98 percent. The compound appears in foods such as fresh fruits, vegetables, and meats, although cooking and processing can lower amounts. Oral, topical, and inhaled forms are discussed in research and consumer contexts, but absorption and tissue delivery remain active areas of study. Regulatory status varies by country and intended use.
Glutathione supports detoxification by conjugating reactive electrophiles through glutathione S-transferases. The resulting conjugates are processed and exported, often after further metabolism. It also stores cysteine, transports amino acids across membranes through the gamma-glutamyl cycle, and assists in the maturation of iron-sulfur clusters and some prostaglandins. In plants, animals, and many microbes, the molecule appears in similar roles, but concentrations vary enormously between tissues. Liver, kidney, and red blood cells tend to contain high amounts, while blood plasma contains much less.
Glutathione is a small tripeptide built from glutamate, cysteine, and glycine. The peptide bond between glutamate and cysteine uses the gamma-carboxyl group, a linkage that resists ordinary peptidases. Cells make it in two ATP-dependent steps: gamma-glutamylcysteine synthetase joins glutamate and cysteine, then glutathione synthetase adds glycine. The pathway is feedback-inhibited by glutathione itself, so intracellular levels tend to stay within a narrow range. Because cysteine is often limiting, sulfur amino acid supply influences how much glutathione a cell can produce.
In its reduced form, glutathione carries a sulfhydryl group that can donate electrons. This property lets it act as a major cellular antioxidant and redox buffer. Glutathione peroxidase uses it to reduce hydrogen peroxide and lipid peroxides, while glutathione reductase regenerates the reduced form using NADPH. The ratio of reduced glutathione to glutathione disulfide is widely used as an indicator of oxidative stress, though the ratio changes with compartment, cell type, and sample handling. Oxidized glutathione can also form mixed disulfides with proteins, affecting their activity.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C10H17N3O6S | Reduced glutathione (GSH) |
| Molar mass | 307.32 g/mol | Oxidized dimer GSSG is 612.63 g/mol |
| Appearance | White to off-white crystalline powder | Typical purified solid |
| Solubility | Freely soluble in water; practically insoluble in ethanol | Polarity reflects multiple ionizable groups |
| Common synonyms | GSH; L-glutathione; γ-glutamylcysteinylglycine | 'Reduced' distinguishes it from GSSG |
Storage conditions strongly influence glutathione stability. The solid reduced form is commonly kept desiccated at or below minus twenty degrees Celsius, protected from light and moisture. Aqueous solutions are less stable because the thiol group reacts with dissolved oxygen, and oxidation accelerates at neutral or alkaline pH. Acidic solutions and oxygen-free handling can slow degradation, but repeated freeze-thaw cycles should be avoided. Researchers often verify concentration before use, because apparent losses can arise from oxidation or water uptake.
Measuring glutathione in biological samples requires attention to oxidation and matrix effects. High-performance liquid chromatography with ultraviolet or fluorescence detection can separate reduced and oxidized forms after derivatization. Liquid chromatography with tandem mass spectrometry offers higher specificity and can quantify glutathione alongside related thiols. Because glutathione can oxidize during sample handling, many protocols use rapid acidification with metaphosphoric acid or sulfosalicylic acid. Internal standards help correct for losses during extraction and analysis.
Biosynthesis proceeds in two ATP-dependent steps. First, glutamate-cysteine ligase joins glutamate and cysteine. Second, glutathione synthetase adds glycine to the intermediate. The pathway is regulated by cysteine availability, enzyme expression, and feedback inhibition by glutathione itself. Liver tissue has a particularly high capacity for synthesis and export. Because the molecule is made inside cells, circulating glutathione reflects a balance of release, uptake, and breakdown rather than simple dietary supply.
Functionally, glutathione supports redox balance by donating electrons and becoming oxidized. It also serves as a cofactor for enzymes such as glutathione peroxidases and glutathione S-transferases. These enzymes participate in peroxide reduction and in conjugation reactions that help process reactive molecules. Separate from antioxidant roles, glutathione can modify protein cysteines through S-glutathionylation, influencing enzyme activity and signaling. Research continues to examine how these chemical roles translate into whole-organism effects.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. Its glutamate-cysteine linkage uses the gamma-carboxyl group of glutamate, a feature that resists standard peptidases. The cysteine residue provides a thiol group, which gives the molecule its reducing character. In cells, glutathione is often the most abundant small-molecule thiol, with concentrations varying widely by tissue and compartment. It exists mainly in a reduced form called GSH, while oxidation produces a disulfide-linked dimer called GSSG.
Tissue engineering aims to generate functional constructs which could replace or improve damaged or infected tissues or whole organs. Many of these constructs lead to infected tissue around the implant area. Coating these materials in amylopectin allows reduction in this infectious reaction. Since amylopectin is mainly used as a coating around these constructs in as it prevents following immune reactions. Since amylopectin is derived directly from a natural polysaccharide, it integrates well with tissues and cells. However, mechanical properties of amylopectin are not optimal due to its high level of crosslinking. This can be avoided by the formation of amylopectin fibers or by forming a nanocomposite with another more rigid polymer.
46. Int J Pharm Compd. 2026 Jul-Aug;30(4):329-336. Synthetic Peptides in Pharmacy Compounding: Analysis of PCAC Recommendations and Industry Safety Standards. Willis J(1), Vu N(2)(3). Author information: (1)University of Oklahoma College of Pharmacy. (2)ARL Bio Pharma, Oklahoma City, Oklahoma. Nvu@arlok.com. (3)University of Oklahoma College of Pharmacy, Oklahoma City, Oklahoma. Compounded peptides have quickly moved from a niche topic to a growing area of interest among patients and prescribers. These products are promoted for a wide range of uses, including tissue repair, inflammation, metabolic health, and healthy aging. This article examines the proposed uses of these peptides, the concerns raised during the review, and the practical implications for compounders. Copyright© by International Journal of Pharmaceutical Compounding, Inc.
=== Wound healing === As a component of skin tissue, collagen is a base material for medical products to support wound healing. When collagen is made available to the wound bed, closure can occur, avoiding wound deterioration and severe surgical procedures, such as amputation. Collagen is used as a natural wound dressing because it has properties that artificial wound dressings do not have. It resists bacteria, which is vitally important in wound dressing. As a burn dressing, collagen aids healing by enabling granulation tissue to grow over the burn. Throughout the four phases of wound healing, collagen performs the following functions:
=== Coordination compounds === In an acidic aqueous solution, thorium occurs as the tetrapositive aqua ion [Th(H2O)9]4+, which has tricapped trigonal prismatic molecular geometry: at pH < 3, the solutions of thorium salts are dominated by this cation. The Th4+ ion is the largest of the tetrapositive actinide ions, and depending on the coordination number can have a radius between 0.95 and 1.14 Å. It is quite acidic due to its high charge, slightly stronger than sulfurous acid: thus it tends to undergo hydrolysis and polymerisation (though to a lesser extent than Fe3+), predominantly to [Th2(OH)2]6+ in solutions with pH 3 or below, but in more alkaline solution polymerisation continues until the gelatinous hydroxide Th(OH)4 forms and precipitates out (though equilibrium may take weeks to be reached, because the polymerisation usually slows down before the precipitation). As a hard Lewis acid, Th4+ favours hard ligands with oxygen atoms as donors: complexes with sulfur atoms as donors are less stable and are more prone to hydrolysis. High coordination numbers are the rule for thorium due to its large size. Thorium nitrate pentahydrate was the first known example of coordination number 11, the oxalate tetrahydrate has coordination number 10, and the borohydride (first prepared in the Manhattan Project) has coordination number 14. These thorium salts are known for their high solubility in water and polar organic solvents.
== History == Insulin was discovered by Sir Frederick G Banting, Charles H Best, and JJR Macleod from the University of Toronto in 1921 as an injectable agent. German researchers first introduced the idea of inhalable insulin in 1924. Years of failure followed until scientists realized they might be able to use new technologies to turn insulin into a concentrated powder with particles sized for inhalation. In the 1980s Nektar Therapeutics, based on work by A. Carl Leopold on vitrifying proteins, developed technology to make insulin into small particles, technology then licensed to Pfizer. Alkermes developed a delivery device that they licensed to Eli Lilly and Company. Once concrete methods were developed, human tests began in the late 1990s. In January 2006, the U.S. Food and Drug Administration (FDA) approved the use of Exubera, a form of inhalable insulin developed by Pfizer. It was approved in the UK in August 2006 but reimbursed by the National Health Service only for people who had problems with needles. It was not reimbursed by any U.S. insurer. A 2007 systematic review concluded that the inhaled hexameric insulin (Exubera) "appears to be as effective, but no better than injected short-acting insulin. The additional cost is so much more that it is unlikely to be cost-effective." In 2007, Pfizer announced that it would no longer manufacture or market Exubera. According to Chairman and CEO Jeffrey Kindler this was because Exubera "failed to gain acceptance among patients and physicians".
Sources: en.wikipedia.org
== Honors and awards == Albania: On 20 June 2008 received a copy of the key of the city of Tirana on the occasion of his state visit to Albania. Also on 20 June, Thaçi was awarded the Honorary Citizen of the city of Vlorë for his "historic role in making Kosovo an independent state". In January 2015 Thaçi was awarded the Doctor Honoris Causa from the University of Tirana for his contribution in peace-building in Western Balkans, promoting the process of European integration and achieving the historic Brussels Agreement with Serbia. On 4 October 2016 he was awarded honorary citizenship of Shkodër in a ceremony led by the mayor of the northern Albanian city. Switzerland: On 1 July 2012, Thaçi received a doctor honoris causa as a doctor of international relations from the Geneva School of Diplomacy. Montenegro: On 4 April 2015, on Ulcinj Day, Thaçi received the title of Honorary Citizen of Ulcinj by the town's municipal government.
== Etymology and pronunciation == The word purpura () comes from Latin purpura, "purple", which came from ancient Greek πορφύρα. Purpura is a mass noun naming the condition or state, not the name of an individual spot (thus there is no *purpurum, *purpura or *purpura, *purpurae count declension).
First, increased dynorphin levels block the release of glutamate, a neurotransmitter involved in plasticity in the hippocampus, which would inhibit new learning. Blocking dynorphin effects would allow glutamate to be released and restore functional plasticity in the hippocampus, reversing the phenomenon of learned helplessness. In addition, blocking dynorphin would enhance dopamine signaling and thus reduce depressive symptoms associated with stress. The authors suggest that KOR antagonists might have potential in treating depression in humans.
Training, HRD and R&D Committee. Committee for Strengthening Supply Chain & Logistics. Application of Non-conventional Energy Sources in Cold Chain Infrastructure. Technical Specification, Standards, Test Laboratory and Product Certification Committee. These committees contribute towards this nodal body's functioning along its road-map.
The two amphetamine enantiomers that compose Adderall, such as Adderall tablets/capsules (levoamphetamine and dextroamphetamine), alleviate the symptoms of ADHD and narcolepsy by increasing the activity of the neurotransmitters norepinephrine and dopamine in the brain, which results in part from their interactions with human trace amine-associated receptor 1 (hTAAR1) and vesicular monoamine transporter 2 (VMAT2) in neurons. Dextroamphetamine is a more potent CNS stimulant than levoamphetamine, but levoamphetamine has slightly stronger cardiovascular and peripheral effects and a longer elimination half-life than dextroamphetamine. The active ingredient in Adderall, amphetamine, shares many chemical and pharmacological properties with the human trace amines, particularly phenethylamine and N-methylphenethylamine, the latter of which is a positional isomer of amphetamine. In 2023, Adderall was the fifteenth most commonly prescribed medication in the United States, with more than 32 million prescriptions.
Sources: en.wikipedia.org
ELGA LabWater is the laboratory water brand name of Veolia Water Solutions & Technologies. ELGA manufactures, supplies and services water purification systems for use in general, R&D, healthcare and clinical laboratories. Its offices and distributors are located in more than 60 countries.
== Honors and awards == Meldal was awarded the 2022 Nobel Prize in Chemistry, jointly with Carolyn R. Bertozzi and Karl Barry Sharpless, "for the development of click chemistry and bioorthogonal chemistry".
== Contraindications == Sertraline is contraindicated in individuals taking monoamine oxidase inhibitors or the antipsychotic pimozide. Liquid formulations of sertraline contain ethanol and are therefore contraindicated with disulfiram. The prescribing information recommends that treatment of the elderly and patients with liver impairment "must be approached with caution". Due to the slower elimination of sertraline in these groups, their exposure to sertraline may be as high as three times the average exposure for the same dose.
First line treatment for metastatic breast cancer: the MARIANNE study compares taxane (docetaxel or paclitaxel) plus trastuzumab vs T-DM1 vs T-DM1 plus pertuzumab as first-line treatment for people with HER2 positive unresectable locally advanced or metastatic breast cancer; On 19 December 2014, Roche reported the results of the MARIANNE study. Neither Kadcyla-containing treatment significantly improved progression-free survival compared to Herceptin and chemotherapy. a phase III trial for HER2+ gastric cancer compares T-DM1 to physician's choice of taxane (docetaxel or paclitaxel). On 22 October 2015, Roche and co-developer ImmunoGen disclosed that trastuzumab emtansine had failed to meet its primary endpoint in the Phase II/III GATSBY trial investigating the second line treatment of HER2-positive advanced gastric cancer. the TH3RESA study is comparing T-DM1 vs treatment of physician's choice for people with HER2 positive metastatic breast cancer previously treated with trastuzumab and lapatinib. Interim results for TH3RESA suggest a doubling of progression-free survival from three months to six months.
Sources: en.wikipedia.org
It is a tripeptide rather than a full protein. Proteins generally contain many amino acids joined by alpha-peptide bonds, while glutathione has three residues and an unusual gamma-glutamyl linkage. That structure affects how enzymes recognize and break it down.
GSH is the reduced form with a free thiol group. GSSG is the oxidized disulfide dimer formed when two GSH molecules react. The GSH-to-GSSG ratio is used in research as one indicator of cellular redox conditions.
Yes, it is present in many animal and plant tissues, including meats, some vegetables, and fruits. Heat, storage, and processing can reduce its content, so measured amounts vary widely.
It is a tripeptide of glutamate, cysteine, and glycine. The glutamate-cysteine bond is unusual because it forms through the gamma-carboxyl group.