Molecular Formula: C5H11NO2S
Molecular Weight: 149.21
CAS No: 63-68-3
L-Methionine | CP2020 | EP11 | USP2023 | USP40 | AJI92 |
Assay | ≥98.5% | 99.0-101.0% | 98.5-101.5% | 98.5-101.5% | 99.0-100.5% |
PH | 5.6-6.1 | 5.5-6.5 | 5.6-6.1 | 5.6-6.1 | 5.6-6.1 |
Specific rotation[a]D20 | +21.0°-+25.0° | +22.5°-+24.0° | / | / | +23.0°-+24.5° |
Specific rotation[a]D25 | / | / | +22.4°-+24.7° | +22.4°-+24.7° | / |
Transmittance(T430) | ≥98.0% | / | / | / | ≥98.0% |
Appearance of solution | / | clear & colorless | / | / | / |
Chloride(Cl) | ≤0.02% | ≤0.02% | ≤0.05% | ≤0.03% | ≤0.02% |
Ammonium(NH4) | ≤0.02% | ≤0.02% | / | ≤0.02% | |
Sulfate(SO4) | ≤0.02% | ≤0.03% | ≤0.03% | ≤0.03% | ≤0.02% |
Iron(Fe) | ≤15PPM | ≤10PPM | ≤30PPM | ≤30PPM | ≤10PPM |
Heavy metals(Pb) | ≤10PPM | / | / | ≤15PPM | ≤10PPM |
Arsenic | ≤1PPM | / | / | / | ≤1PPM |
Other amino acids | ≤0.5% | Each impurity≤ 0.1% Total impurities≤ 0.3% | Methionine sulfoxide≤0.1% N-Acetyl-D,L-methionine≤0.2% Any unspecified impurity≤0.1% Total unspecified impurities≤0.3% | Individual impurities≤0.5% Total impurities≤2.0% | conforms |
Ninhydrin-positive substances | / | / | / | / | / |
Loss on drying | ≤0.2% | ≤0.50% | ≤0.3% | ≤0.3% | ≤0.20% |
Residue on ignition | ≤0.1% | ≤0.10% | ≤0.4 | ≤0.4 | ≤0.10% |
Endotoxin | <25 EU/g | <25 EU/g | <25 EU/g | / | / |
Total plate count | ≤ 1000 CFU/g | ≤ 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 | ≤ 100 CFU/g |