1.02839

L-Cysteine hydrochloride monohydrate

for biochemistry

• Synonym(s): Cys, L-Cysteinium Chloride Monohydrate, L-Cysteine Hydrochloride, Monohydrate
• Linear Formula: HSCH₂CH(NH₂)COOH · HCl · H₂O
• CAS Number: 7048-04-6
• Molecular Weight: 175.63
• Beilstein/REAXYS Number: 5158059
• MDL number: MFCD00065606
• UNSPSC Code: 12352209
• EC Index Number: 200-157-7
• NACRES: NA.21

Properties

• vapor pressure: <0.1 hPa ( 20 °C)
• Quality Level: 100
• assay: 98.5-101.0% dry basis (alkalimetric)
• form: crystalline powder
• pH: 0.8-1.2 (20 °C, 100 g/L in H₂O)
• mp: 168-170 °C
• solubility: 650 g/L
• density: 1.54 g/cm³
• bulk density: 780 kg/m³
• anion traces: sulfate (SO₄^2-): ≤300 ppm
• cation traces: Fe: ≤20 ppm; heavy metals (as Pb): ≤10 ppm
• storage temp.: 2-30°C
• SMILES string: O.Cl.N[C@@H](CS)C(O)=O
• InChI: 1S/C3H7NO2S.ClH.H2O/c4-2(1-7)3(5)6;;/h2,7H,1,4H2,(H,5,6);1H;1H2/t2-;;/m0../s1
• InChI key: QIJRTFXNRTXDIP-JIZZDEOASA-N

Description

Application

• Smartphone-based Ellman′s colourimetric methods for the analysis of d-penicillamine formulation and thiolated polymer: Demonstrates the application of L-Cysteine hydrochloride monohydrate in developing colorimetric assays for pharmaceutical analysis, enhancing the accessibility and cost-effectiveness of drug quality control (Phadungcharoen et al., 2019).


• The effects of the thiolation with thioglycolic acid and l-cysteine on the mucoadhesion properties of the starch-graft-poly(acrylic acid): Focuses on the modification of polymers with L-Cysteine hydrochloride monohydrate to improve their mucoadhesive properties, which is critical for developing more effective drug delivery systems (Gök et al., 2017).


• On-line pre-reduction of pentavalent arsenicals by thioglycolic acid for speciation analysis by selective hydride generation-cryotrapping-atomic absorption spectrometry: Utilizes L-Cysteine hydrochloride monohydrate in analytical chemistry techniques to improve the detection and measurement of toxic elements in environmental samples, crucial for monitoring and ensuring public health (Musil et al., 2008).

Biochem/physiol Actions

NMDA glutamatergic receptor antagonist.

Analysis Note

Assay (alkalimetric, calculated on dried substance): 98.5 - 101.0 %
Identity (IR-spectrum): passes test
Identity (Chloride): passes test
Appearance: white or almost white, crystalline powder or colorless crystals
Appearance of solution (25 g/l, water): clear and not more intense in color than reference solution BY6
Spec. rotation (α 20/D, 80 g/l, hydrochloric acid 250 g/l, calc. on dried substance): +5.5 to +7.0
Spec. rotation (α 25/D, 80 g/l, hydrochloric acid 6 mol/l, calc. on dried substance): +5.7 to +6.8
Sulfate (SO₄): ≤ 300 ppm
Heavy metals (as Pb): ≤ 10 ppm
Fe (Iron): ≤ 20 ppm
Related Compounds, total (TLC): ≤ 0.5 %
Ninhydrin-positive substances (LC)(impurity A (570 nm)): ≤ 0.5 %
Ninhydrin-positive substances (LC)(any ninhydrin-positive impurity): ≤ 0.2 %
Ninhydrin-positive substances (LC) (ammonium (570 nm)): ≤ 0.02 %
Ninhydrin-positive substances (LC)(total impurities): ≤ 1.0 %
Residual solvents (ICH Q3C): excluded by manufacturing process
Sulfated ash (600 °C): ≤ 0.1 %
Loss on drying (Vacuum < 0.7 kPa, P₂O₅, 24 h): 8.0 - 12.0 %
Bacterial endotoxins: ≤ 6.0 I.U./g

Safety Information

• Storage Class: 11 - Combustible Solids
• wgk_germany: WGK 1
• flash_point_f: Not applicable
• flash_point_c: Not applicable