CAS number： 79-57-2
Molecular formula： C22H26N2O8
molecular weight： 446.4504
Chemical structure：
| Name of Product: | Oxytetracycline Dihydrate | |
| Shelf Life: | 4 years | |
| Specification: | BP2011 | |
| Test Items | Specification | Results of Analysis |
| Characters | Yellow crystalline powder | Conform |
| Identification | A.Thin-layer chromatography results | Conform |
| B.A deep red colour develops in sulfuric acid and it becomes yellow when being diluted with water | Conform | |
| C.Reaction of chlorides | Conform | |
| Ph | 4.5 to 7.5 | 5.5 |
| Specific optical rotation | -203 to -216 | -210° |
| Specific absorbance | 290 to 310 | 304 |
| Light-absorbing impurities | 430nm≤0.25 | 0.12 |
| 490nm≤0.20 | 0.14 | |
| Related substances | content of impurity peak meets the requirements | Conform |
| Heavy metals (ppm) | ≤50 | ＜50 |
| Water (%) | 6.0 to 9.0 | 7.5 |
| Sulfated ash (%) | ≤0.5 | 0.1 |
| Assay (%) | 95.0 to 102.0 | 97.2 |
