Glutathione (GSH)¶
Glutathione (γ-L-glutamyl-L-cysteinylglycine, GSH, CAS 70-18-8) is the most abundant endogenous intracellular antioxidant, a tripeptide with a molecular weight of approximately 307.3 Da and formula C₁₀H₁₇N₃O₆S. Synthesized in virtually all mammalian cells through two sequential ATP-dependent enzymatic reactions (γ-glutamylcysteine synthetase and glutathione synthetase), GSH exists at millimolar concentrations (1–10 mM) in the cytosol. It is a fundamental research tool in redox biology, oxidative stress, and cellular detoxification mechanisms.
Technical Specifications¶
| Property | Value |
|---|---|
| CAS Number | 70-18-8 |
| Molecular Formula | C₁₀H₁₇N₃O₆S |
| Molecular Weight | ~307.3 Da |
| Purity | ≥99% (HPLC-verified) |
| Appearance | Lyophilized white powder |
| Solubility | Highly soluble in sterile water and aqueous buffers |
| Storage | -20°C (lyophilized), 2–8°C (reconstituted) |
Mechanism of Action¶
Glutathione functions as the principal cellular redox buffer through reversible oxidation of its cysteinyl thiol group. Reduced glutathione (GSH) donates electrons to neutralize reactive oxygen species (ROS) — including superoxide (O₂⁻), hydrogen peroxide (H₂O₂), and hydroxyl radicals (·OH) — either directly or through its role as a co-substrate for glutathione peroxidase (GPx) enzymes. The resulting oxidized glutathione (GSSG) is recycled back to GSH by glutathione reductase using NADPH as the electron donor, maintaining the crucial GSH:GSSG ratio (typically >100:1) that defines cellular redox status. Beyond direct antioxidant defense, GSH serves as a cofactor for glutathione S-transferase (GST)-mediated detoxification of xenobiotics, electrophilic compounds, and lipid peroxidation products through conjugation reactions. GSH also maintains the reduced state of protein thiols through glutaredoxin-mediated deglutathionylation, regulates cell proliferation and apoptosis via redox-sensitive transcription factors (NF-κB, AP-1, Nrf2), and participates in leukotriene and prostaglandin biosynthesis as a co-substrate. The γ-glutamyl bond (rather than the standard α-peptide bond) confers resistance to intracellular peptidases.
Research Applications¶
- Primary: Redox biology — oxidative stress, GSH/GSSG ratio, cellular antioxidant defense
- Secondary: Xenobiotic detoxification and GST-mediated conjugation, apoptosis and cell death signaling, mitochondrial redox homeostasis
- Model Systems: In vitro (all mammalian cell types, isolated mitochondria, GSH depletion models using BSO), in vivo (oxidative stress models, acetaminophen-induced hepatotoxicity, ischemia-reperfusion)
Quality Control & Analytical Methods¶
- HPLC: ≥99% purity verification at 214/220 nm (C18 reversed-phase column)
- Mass Spectrometry: ESI-MS for molecular weight confirmation (~307.3 ±1.0 Da)
- Peptide Content: Amino acid analysis (AAA) for net peptide content determination
- Endotoxin: <1 EU/mg (LAL assay)
- TFA Content: <1% (ion chromatography)
Stability & Storage¶
| Condition | Stability |
|---|---|
| -20°C (lyophilized) | 24 months |
| 4°C (lyophilized) | 6 months |
| 25°C (lyophilized) | 1 month |
| Reconstituted (4°C) | 7 days |
| Reconstituted (-20°C) | 30 days |
Key Research References¶
- Meister & Anderson (1983) — Glutathione. Annu Rev Biochem. PMID: 6137189
- Forman et al. (2009) — Glutathione: overview of its protective roles, measurement, and biosynthesis. Mol Aspects Med. PMID: 18712089
- Lu (2013) — Glutathione synthesis. Biochim Biophys Acta. PMID: 22995213
Source & Purchase¶
For researchers requiring research-grade GLUTATHIONE with full analytical documentation including HPLC, LC-MS, and Certificate of Analysis, visit the HK Peptides product page for specifications, bulk pricing, and ordering.
Related Molecules¶
- NAD+ — Cellular energy coenzyme, redox partner
- SS-31 — Mitochondrial cardiolipin protection
- GHK-Cu — Copper tripeptide, superoxide dismutase-like activity
- All Product Specifications
FAQ¶
Q: What purity level is standard for Glutathione? A: HK Peptides supplies Glutathione at ≥99% purity by HPLC with full COA documentation.
Q: How should Glutathione be stored for research use? A: Lyophilized Glutathione should be stored at -20°C, protected from moisture. Reconstituted solutions at 4°C for short-term use (up to 7 days). Note: GSH slowly oxidizes to GSSG in solution at neutral pH.