L-Cysteine Monohydrochloride CAS 52-89-1

1. L-Cysteine monohydrochloride is a sulfur-containing amino acid derivative used as a reducing agent in biochemical applications to protect proteins and enzymes from oxidation and to maintain thiol groups in a reduced state .
2. L-Cysteine monohydrochloride CAS 52-89-1 serves as a pharmaceutical ingredient in the treatment of bronchopulmonary diseases, where it functions as a mucolytic agent to reduce sputum viscosity and improve airway clearance .
3. L-Cysteine monohydrochloride is employed in the food industry as a dough conditioner, flavor enhancer, and antioxidant, and in cosmetic formulations for hair straightening and skin care products .
4. Researchers utilize L-Cysteine monohydrochloride CAS 52-89-1 as a building block in peptide synthesis, as a reference standard in amino acid analysis, and in cell culture media to promote cell growth and viability .

1. L-Cysteine monohydrochloride must be stored in a tightly sealed container in a cool, dry, and well-ventilated environment, protected from light and moisture; powder is stable for up to 3 years at -20°C or 2 years at 4°C .
2. L-Cysteine monohydrochloride CAS 52-89-1 is classified with GHS hazard statements H315 (Causes skin irritation), H319 (Causes serious eye irritation), and H335 (May cause respiratory irritation), with signal word "Warning" .
3. Personnel must wear chemical-resistant gloves, safety goggles with side-shields, and protective clothing when handling this substance, ensuring adequate ventilation in work areas .
4. Keep L-Cysteine monohydrochloride CAS 52-89-1 away from incompatible materials such as strong oxidizing agents, strong acids, and strong bases to prevent decomposition; L-cysteine monohydrochloride is sensitive to oxidation and should be stored under inert atmosphere .

1. Isolate the spill area, ensure adequate ventilation, and wear full personal protective equipment including chemical-resistant gloves, safety goggles, and suitable dust respirator when L-Cysteine monohydrochloride is released .
2. Collect L-Cysteine monohydrochloride CAS 52-89-1 by sweeping or vacuuming without creating dust using non-sparking tools, and place into suitable closed containers for disposal .
3. Avoid creating dust clouds during cleanup to prevent respiratory exposure; prevent the product from entering drains or water courses .
4. Dispose of collected material according to local, state, and federal environmental regulations through licensed chemical destruction or controlled incineration .

1. L-Cysteine monohydrochloride is not classified as highly flammable but may decompose under fire conditions, emitting toxic fumes including carbon monoxide, carbon dioxide, nitrogen oxides (NOx), sulfur oxides, and hydrogen chloride .
2. Use water spray, dry chemical powder, carbon dioxide, or alcohol-resistant foam to extinguish fires involving the product; do NOT use a direct water jet as L-Cysteine monohydrochloride CAS 52-89-1 may scatter burning material .
3. Firefighters should wear self-contained breathing apparatus in pressure-demand, MSHA/NIOSH approved, and full protective gear when handling burning L-Cysteine monohydrochloride due to hazardous decomposition gases generated by thermal decomposition .
4. During combustion, may emit irritant and toxic fumes; contain fire runoff to prevent environmental contamination .