| Test items | In-house Standard | Test results |
|---|---|---|
| Description | White crystals or crystalline powder | Conforms |
| Identification | Infrared absorption | Conforms |
| Solubility | Almost insoluble in water, almost insoluble in 96% ethanol and ether | Conforms |
| Assay | 99.0~101.0% | 99.50% |
| Loss on drying | ≤12.0% | 10.20% |
| Residue on ignition | ≤0. 10% | 0.08% |
| pH | 2.2~3.0 | 2.7 |
| Chloride | ≤100ppm | ＜100ppm |
| Individual impurities | ≤0.1% | ＜0.1% |
| Total impurities | ≤0.3% | ＜0.3% |
| Heavy metals | ≤20ppm | ＜20ppm |
| Lead | ≤1ppm | ＜1ppm |
| Cadmium | ≤0.5ppm | ＜0.5ppm |
| Mercury | ≤0.1ppm | ＜0.1ppm |
| Arsenic | ≤1ppm | ＜1ppm |
