L-Cysteine 
Molecular Formula: C6H12N2O4S2
Molecular Weight: 240.29
Cas No: [56-89-3]
Characteristics: White crystals or crystalline powder; tasteless. Practically insoluble in water, in ethanol and in ether. Dissolves in dilute HCl.
Quality Standards: AJI92, FCCIV, In-house (ref USP24)
| Item | Specifications (AJI92 ) | USP 24 | FCC IV |
| Appearance | White crystal or crystalline powder; tasteless | ||
| Description | White crystals or crystalline powder | ||
| Identification | Infrared absorption spectrum | ||
| Specific
rotation [a]D20° |
-215 °- -225 ° | -215 ° - -225 ° | -215 ° - -225 ° |
| State
of solution (Transmittance) |
≥ 98.0% | --- | --- |
| Chloride(CL) | ≤ 0.020% | ≤ 0.020% | --- |
| Ammonium(NH4) | ≤ 0.02% | --- | --- |
| Sulfate(SO4) | ≤ 0.020% | ≤ 0.020% | --- |
| Iron(Fe) | ≤ 20PPm | ≤ 20PPm | --- |
| Heavy metals(Pb) | ≤ 10PPm | ≤ 10PPm | 20ppm |
| Arsenic(As2O3) | ≤ 1PPm | --- | --- |
| Other amino acids | Conforms | --- | --- |
| Loss on drying | ≤ 0.20% | ≤ 0.20% | ≤ 0.20% |
| Residue on ignition (Sulfated) | ≤ 0.10% | ≤ 0.10% | ≤ 0.10% |
| Assay | 98.5-101.0% | 98.5-101.0% | 98.5-101.0% |
| PH | 5.0-6.5 | 5.0-6.5 | --- |
| Organic
Volatile impurities |
--- | Meets the requirements | --- |
Packaging and Storage: In
25kgs f iber drum double polyethylene bags inside; Preserve in well-closed
containers, at controlled room temperature.
Recommended limit: 1 year.
