Molecular Formula: C6H12N2O4S2
Molecular Weight: 240.3
CAS No: 56-89-3
| L-Cystine | EP11 | USP2023 | AJI92 | FCC11 |
| Assay | 98.5-101.0% | 98.5-101.5% | 98.5-101.0% | 98.5-101.5% |
| PH | / | / | 5.0-6.5 | / |
| Specific rotation[a]D20 | -218°--224° | -215°--225° | -215°--225° | -215°--225° |
| Specific rotation[a]D25 | / | / | / | / |
| Transmittance(T430) | / | / | ≥98.0% | / |
| Appearance of solution | clear & colorless≤Y7 | / | / | / |
| Chloride(Cl) | ≤0.02% | ≤0.02% | ≤0.02% | / |
| Ammonium(NH4) | ≤0.02% | / | ≤0.02% | / |
| Sulfate(SO4) | ≤0.03% | ≤0.02% | ≤0.02% | / |
| Iron(Fe) | ≤10PPM | ≤10PPM | ≤20PPM | / |
| Heavy metals(Pb) | / | / | ≤10PPM | ≤5PPM |
| Arsenic | / | / | ≤1PPm | / |
| Other amino acids | / | Individual impurities≤0.2% Total impurities≤2.0% | conform | / |
| Ninhydrin-positive substances | Each impurity≤0.2% Total impurities≤0.5% | / | / | / |
| Loss on drying | ≤0.50% | ≤0.20% | ≤0.20% | ≤0.20% |
| Residue on ignition | ≤0.10% | ≤0.10% | ≤0.10% | ≤0.10% |
| Total plate count | ≤ 1000 CFU/g | ≤ 1000 CFU/g | ≤ 1000 CFU/g | ≤ 1000 CFU/g |
| Moulds & Yeasts | ≤ 100 CFU/g | ≤ 100 CFU/g | ≤ 100 CFU/g | ≤ 100 CFU/g |