Appearance: A yellow crystalline powder
Identification
A): TR of HPLC test
B): Sulphuric acid yellow color reaction
C): Chloride's reaction
pH: 2.0 to 3.0
Specific optical rotation: -105 to -120, calculated on the anhydrous, ethanol-free substance
Specific absorbance: 300 to 335 at 349nm, calculated on the anhydrous, ethanol-free substance
Light-absorbing impurities: Not more than 0.07 at 490nm, calculated on the anhydrous, ethanol-free substance
Related substances
Metacyclin: Not more than 2.0%
6-epidoxycycline: Not more than 2.0%
Any other impurities: Not more than 0.5%
Ethanol: 4.3 to 6.0%
Heavy metals: Not more than 50ppm
Water: 1.4 to 2.8%
Sulfated ash: Not more than 0.4%
Assay: 95.0% to 102.0%