L-arginine

L-Arginine (CAS 74-79-3), commonly abbreviated as L-Arg, is a conditionally essential amino acid. FEMA 3819.

Where is L-arginine used?

• Pharmaceutical manufacturing: solubilizes poorly water-soluble active ingredients
• Pharmaceutical manufacturing: stabilizes protein-based drug formulations, including injectables and biologics
• Reduces viscosity in high-concentration protein formulations.
• Sports nutrition and dietary supplements: pre-workout powders, capsules, and functional beverages
• Food: flavor precursor in processed and heat-treated products where controlled Maillard reaction development is required
• Personal care: pH adjuster and humectant in skin creams, hair conditioners, and scalp treatments
• In cosmetics, functions as an antistatic agent.
• It functions as a pH buffer, stabilizer, and bioavailable nitrogen source in formulated products.

Good to know: The hydrochloride form is commonly preferred for pharmaceutical applications requiring precise pH control.

Formulation notes

• May be incompatible with acidic excipients.
• pH control is important for solutions because they are strongly basic.
• The HCl form is the monohydrochloride salt (CAS 1119-34-2), is more water-soluble than the free base, and differs in mass per unit of arginine and in solution pH profile.
• Formulators choose between the free base and the HCl salt based on solubility, pH and dosing needs, and both forms are stocked.

Typical specification

• Classified under HS subheading 2922.49.
• Sold with a purity of 99.89%.

Regulatory status

• Has ATC codes V03AF11 and B05XB01.
• Listed as a JECFA flavouring substance.

Storage, packaging and handling

• Should be protected from direct sunlight.

Frequently asked questions about L-arginine

Which pharmacopoeial standards does L-arginine meet?

It is supplied compliant with the EP, USP, JP and ChP pharmacopoeias.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.