| Items | Specifications |
| Appearance | A white or almost white crystalline powder |
| Identification | A) IR B) TLC C) UV-Vis: There is a maximum absorbance at 210nm |
| pH | 2.0 ~ 3.0 |
| Clarity and color | Comply with requirements |
| Loss on drying | 5.0% ~ 7.0% |
| Chloride | ≤0.02% |
| Phosphate | ≤0.5% |
| Heavy metals | ≤0.002% |
| Phosphite | ≤0.5% |
| Related substances | Individual impurity≤0.25% Total impurities≤0.5% |
| Assay | 98.0% ~ 102.0% |
