Description

L-(-)-Cystine Dihydrochloride is the dihydrochloride salt form of the essential sulfur-containing amino acid L-Cystine. This compound is critical for applications requiring enhanced solubility and stability in aqueous systems compared to the free base form. It is primarily utilized in the pharmaceutical, nutraceutical, and biochemical research sectors. Its role is fundamental in formulations where precise amino acid supplementation and controlled chemical reactivity are required.

Application

• Pharmaceutical Intermediates: Serves as a key chiral building block in the synthesis of active pharmaceutical ingredients (APIs) and peptide-based drugs.
• Cell Culture Media: An essential component in defined media formulations for mammalian cell culture, supporting protein synthesis and cellular growth.
• Dietary Supplements & Nutraceuticals: Used in specialized nutritional products targeting hair, skin, and nail health due to its high sulfur content.
• Biochemical Research: Employed as a standard or reagent in studies of protein structure, disulfide bond formation, and oxidative stress.
• Cosmetic Formulations: Incorporated into high-end skincare and haircare products for its purported antioxidant and strengthening properties.
• Food Fortification: Used in the fortification of certain food products and clinical nutrition formulas.

Basic Information

Product Name	L-(-)-Cystine Dihydrochloride
CAS No.	13059-63-7
Molecular Formula	C6H12N2O4S2 • 2HCl
Molecular Weight	313.22 g/mol
Synonyms	L-Cystine Dihydrochloride; (R,R)-3,3'-Dithiobis(2-aminopropionic acid) dihydrochloride; Dicysteine dihydrochloride; Cystine 2HCl; L-Cystine HCl; (2R,2'R)-3,3'-Disulfanediyldialanine dihydrochloride; L-α-Diamino-β-dithiolactic acid dihydrochloride
EINECS	235-950-8

Quality Control

Our L-(-)-Cystine Dihydrochloride is manufactured under a strict quality management system. Each batch undergoes comprehensive analytical testing to ensure it meets high-purity standards suitable for pharmaceutical and research applications. Certificates of Analysis (COA) detailing purity, identity, and specific impurity profiles are available upon request. We can supply material compliant with various pharmacopeial standards (e.g., USP, EP) based on customer requirements.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at a controlled room temperature (15-25°C). Due to its hygroscopic nature, the container must be kept tightly sealed after opening to prevent moisture absorption, which can affect stability and handling properties.

Specification

Item	Specification
Appearance	White to almost white crystalline powder
Identification (IR)	Conforms
Assay (HPLC)	98.5% - 101.0% (on anhydrous basis)
Specific Rotation [α]20/D	-215° to -225° (c=1 in 1N HCl)
pH (5% solution)	1.5 - 2.5
Loss on Drying	≤ 0.5%
Residue on Ignition (Sulfated Ash)	≤ 0.1%
Heavy Metals (as Pb)	≤ 10 ppm
Related Substances (HPLC)	Total impurities ≤ 1.0%

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.