| Appearance | A white or greyish-white, crystalline powder; odorless. It darkens on exposure to air and light, decomposition being faster in the presence of moistu |
| Assay (on anhydrous basis) | 98.0-101.0% |
| Solubility | Freely soluble in water, slightly soluble in ethanol(95%), practically insoluble in chloroform and in |
| Appearance of solution | To comply IP test |
| Identification A (IR spectrum) | To confirm the structure |
| Identification ‘B’ | Absorption maxima at 279 nm, about 0.4 absorbance |
| Identification ‘C’ | It gives reaction of tartrate |
| Related substance (by HPLC) | |
| Impurity A | Max 0.3% |
| Impurity B, C | Max 0.2% each |
| Total unspecified impurities | Max 0.1% each |
| Total impurities | Max 0.6% |
| Phenones (by UV) | Max 0.1 absorbance at 310 nm |
| Loss on drying | Max 0.5% |
| Sulphated ash | Max 0.1% |
| pH (1% w/v solution) | 2.8 – 4.0 |
| Specific optical rotation ([?]20/D) | -50.0° to -54.0° |
