L-Cysteine, 250 g

A laboratory-grade amino acid supplied by STEMCELL Technologies, identified chemically as (2R)-2-amino-3-sulfanylpropanoic acid (CAS 52-90-4) with the molecular formula C3H7NO2S and a molecular weight of 121.2. The substance is a solid and is freely water-soluble at 280 g/L (25 °C, 77 °F), with slight solubility in PBS (pH 7.2). It is recommended for use as a laboratory chemical and is also referenced under the synonyms L-Cys, L-(+)-Cysteine, (R)-Cysteine, and NSC 8746.

According to the manufacturer's safety data sheet, the chemical is classified as Acute Toxicity – Oral Category 4 and is harmful if swallowed, with an oral LD50 of 1890 mg/kg in the rat. Appropriate handling includes washing face, hands and any exposed skin thoroughly after use and not eating, drinking or smoking while handling the product. In case of ingestion, a poison centre or physician should be contacted and the mouth rinsed; vomiting should not be induced. The material should be stored in accordance with the Product Information Sheet and kept out of the reach of children. It is stable under recommended transport or storage conditions and is incompatible with strong oxidizing agents, with hazardous decomposition products including carbon oxides, nitrogen oxides (NOx) and sulfur oxides.