L-Histidine monohydrochloride monohydrate

L-Histidine monohydrochloride monohydrate (CAS 5934-29-2, EC 611-821-4) is the hydrochloride salt form of the amino acid L-Histidine, commonly abbreviated as L-HIS HCL H2O or L-Histidine HCL Monohydrate. It carries no E-code designation and is distinct from the free base form in its improved aqueous solubility and handling stability.

In pharmaceutical formulations, it functions as a buffering agent to stabilize protein-based biologics and vaccine solutions within a controlled pH range. In personal care, it acts as a humectant and skin conditioner by binding moisture at the stratum corneum level, and its imidazole side chain contributes antioxidant activity by scavenging reactive oxygen species in leave-on and rinse-off products.

This material is available in pharmaceutical and food-grade specifications, compliant with Ph.Eur. and FCC monographs, and falls under REACH registration obligations for EU supply. It is supplied as a crystalline powder, typically in 25 kg bags or fiber drums, with documentation available to support regulatory submissions.