L-Glutathione
Founded in 2017, Sigma Chemical Co., Ltd. supplies over 100 countries with high-quality chemicals. We are dedicated to safety, innovation, and global cooperation.
Product Description
Glutathione is a small peptide composed of glutamic acid, cysteine, and glycine, widely present in human cells and known as the "master antioxidant." Its core functions include powerful antioxidant activity (directly neutralizing free radicals and regenerating other antioxidants), crucial liver detoxification, important immune system support, and participation in cellular metabolism, DNA repair, and mitochondrial protection. Human glutathione levels can decrease due to aging, chronic diseases, stress, poor diet, and exposure to toxins. Supplementation methods include dietary intake (such as consuming sulfur-rich cruciferous and allium vegetables to promote endogenous synthesis), oral supplements (such as novel liposomal or acetylated forms to improve bioavailability), or intravenous injection or nebulization under medical supervision. While it shows potential health benefits in improving fatty liver and supporting the nervous system, and is generally considered safe, evidence for its use in skin whitening and other effects is limited, and potential side effects and drug interactions should be considered. Consultation with a healthcare professional is recommended before use.
Other Information
Analytical Method
Reverse-Phase HPLC is a standard method for quantifying GSH. A typical method uses a C18 column, a mobile phase of TFA in acetonitrile/water, and UV detection at 215 nm.
Mechanism of Enhanced Topical Delivery (GSH-SLN-EH)
- Nanocarrier Advantage: SLNs provide high drug loading, protect GSH, and their nano-size (~200-400 nm) facilitates penetration through the lipid-based stratum corneum.
- Polymer Enhancement: Chitosan (in SLNs) and Carbopol (in hydrogel) act as penetration enhancers and bioadhesives.
- Surfactant Action: Surfactants in the formulation (e.g., Tween 80) can temporarily disrupt skin lipids to enhance diffusion.
- Hydrogel Properties: Provides sustained release, excellent skin contact, adhesion, and improved patient compliance.
Synthesis Methods
Chemical Synthesis:
- L-Glutathione (γ-glutamylcysteinylglycine) is a tripeptide synthesized via the condensation of its constituent amino acids: L-glutamic acid, L-cysteine, and glycine.
- The reduced form (GSH) is the biologically active antioxidant. An oxidized form (GSSG) also exists.
- Commercial Production: It is commonly produced through fermentation using yeast (e.g., Saccharomyces cerevisiae) or via enzymatic synthesis, which are scalable and cost-effective methods for pharmaceutical and commercial use.
Encapsulation/Nanocarrier Production (for topical/drug delivery):
- Solid Lipid Nanoparticles (SLNs): GSH can be encapsulated into SLNs using a double-emulsion (W1/O/W2) technique.
Process: A primary emulsion (W1/O) is formed by sonicating an aqueous GSH solution in a molten lipid phase (e.g., stearic acid) with a surfactant (e.g., Span® 85). This is then emulsified into an external aqueous phase containing a second surfactant (e.g., Tween® 80) and a coating polymer like chitosan. The emulsion is solidified in cold water.
- Hydrogel Formulation: The prepared GSH-loaded SLNs (or free GSH) can be incorporated into a semi-solid hydrogel matrix.
Process: Polymers like Carbopol® 971P NF are swollen in an aqueous buffer (e.g., PBS, pH 5.5). The GSH-SLN powder or GSH is then mixed into the hydrogel under magnetic stirring to form the final enriched hydrogel (GSH-SLN-EH).
Uses and Applications
Pharmaceutical & Cosmetic (Topical/Anti-Ageing):
- Primary Use: Combating skin ageing induced by oxidative stress, particularly from UVA radiation. GSH scavenges reactive oxygen species (ROS) like superoxide and hydroxyl radicals.
- Challenge: Poor stability and limited skin penetration (through the stratum corneum) hinder its direct topical use.
- Solution: Formulating GSH into advanced delivery systems like chitosan-coated SLNs embedded in Carbopol hydrogels significantly enhances its stability, skin penetration (3.7-fold improvement), sustained release (over 72 hours), and antioxidant efficacy at the cellular level.
- Other Potential Topical Applications: Wound healing and inflammatory skin diseases.
Agricultural & Post-Harvest Technology:
Use: As a post-harvest treatment to improve the quality, shelf life, and marketability of perishable fruits (e.g., strawberries, sweet peppers, okra).
Mechanism/Effects:
- Reduces weight loss and water transpiration.
- Enhances antioxidant capacity and levels of beneficial compounds: total phenols, flavonoids, anthocyanins, and ascorbic acid.
- Boosts activity of endogenous antioxidant enzymes: Catalase (CAT), Superoxide Dismutase (SOD), Guaiacol Peroxidase (POD), Ascorbate Peroxidase (APX), and Phenylalanine Ammonia-Lyase (PAL).
- Reduces oxidative damage: Lowers Malondialdehyde (MDA) levels, a marker for lipid peroxidation and cell membrane damage.
Typical Application: Spraying fruits with GSH solutions (optimal concentration found around 64 mM for strawberries) before cold storage.
Energy Technology
Novel Use: As a kinetic promoter for the formation of methane hydrates for natural gas storage (Solidified Natural Gas - SNG technology).
Advantages:
- Highly Effective: Enhances both the formation rate and final gas uptake capacity (up to 139.6 V/V, ~82.4% water conversion).
- Eco-friendly & Foam-Free: Unlike traditional surfactants (e.g., SDS), GSH is biodegradable and allows for foam-free dissociation during gas recovery.
- Good Recyclability: Can be reused over multiple formation-dissociation cycles.
Implications: Promising for large-scale, safe energy storage, carbon capture, and desalination technologies.
General Biochemical & Medical:
- Master Antioxidant: Protects cells from oxidative damage and is involved in detoxification processes in the liver, kidneys, lungs, and intestines.
- Cellular Health: Essential for immune function, DNA synthesis and repair, protein synthesis, enzyme activity, and signal transduction.
- Therapeutic Potential: Studied for roles in managing conditions related to oxidative stress, such as degenerative diseases, certain skin disorders, and heavy metal toxicity.
Properties and Characteristics
Chemical & Physical Properties
- Solubility: Hydrophilic. Soluble in water, dilute alcohols; insoluble in organic solvents like ether.
- Chemical Structure: Tripeptide with a reactive thiol (-SH) group on its cysteine residue, which is responsible for its redox activity.
- Stability: The reduced form (GSH) is unstable in aqueous solutions and susceptible to oxidation and hydrolysis, especially at neutral or alkaline pH and elevated temperatures. Optimal storage is at 4°C.
Functional & Performance Properties
- Antioxidant Capacity: Significantly protects human skin fibroblasts from UVA-induced oxidative stress, enhancing cell viability (up to 370% vs. control).
- Drug Release Profile: When encapsulated in SLN-hydrogels, exhibits sustained and controlled release over 72 hours, following kinetics models like Korsmeyer-Peppas or Higuchi, as opposed to the rapid burst release of free GSH solution.
- Rheological Properties (in hydrogel): The optimal 3% Carbopol hydrogel containing GSH-SLNs exhibits:
- Pseudoplastic & Thixotropic Flow: Shear-thinning behavior, easier spreadability upon application.
- Viscoelasticity: Solid-like elastic behavior (G' > G'') ensuring good stability, with a transition aiding skin spread.
- Mechanical Properties: Good gel strength (~5.1 g), spreadability (~33.6 g·s), and adhesion.
- Promoter Performance (for hydrates): High hydrophilic yet acts as an excellent kinetic promoter for methane hydrate, indicating a complex structure-activity relationship beyond simple hydrophobicity.
Safety and Handling
General Safety
- Biocompatibility: GSH is an endogenous, non-toxic molecule with high biocompatibility.
- Cytotoxicity: Studies show no cytotoxic effects on human skin fibroblasts (Fbs) at tested concentrations. Instead, it shows cytoprotective effects.
- Regulatory Status: Considered safe for use in pharmaceuticals, cosmetics (as an ingredient), and as a dietary supplement. However, specific regulatory approvals apply to its use as a drug or novel food treatment.
Handling and Storage
- Stability: GSH is prone to degradation. Temperature is a critical factor.
Recommended Storage: 4°C is optimal for long-term stability (maintaining chemical integrity and formulation properties over 3 months).
Avoid: Room temperature (25°C) and elevated temperatures (40°C), which accelerate degradation.
- pH Sensitivity: Most stable in acidic conditions. Degradation increases at neutral or alkaline pH.
- Formulation-Dependent: When encapsulated in SLNs and hydrogels, its stability is significantly enhanced against environmental degradation factors.
- Handling Precautions: Standard laboratory practices are sufficient. Use personal protective equipment (gloves, goggles) when handling powders or concentrated solutions to avoid irritation.
- Topical/Pharmaceutical: While the final hydrogel formulation is non-irritating and safe for skin, comprehensive human clinical trials are the next step for validation.
- Agricultural: Follow standard guidelines for post-harvest chemical treatments. The provided research indicates no adverse effects on fruit quality.
- Energy Technology: The foam-free nature of GSH in hydrate dissociation enhances operational safety compared to surfactant-based promoters.
Specific Application Warnings