Erythromycin thiocyanate
Test item: Veterinary Drug Code of the people's Republic of China (Volume I, 2015 Edition)
Properties: This product is white or off white crystalline or crystalline powder; Odorless; Slightly hygroscopic. This product is easily soluble in methanol or ethanol and slightly soluble in water or chloroform.
Identification: weigh 5mg of this product, add 2ml of sulfuric acid, shake it slowly, and it will turn reddish brown. Weigh 5mg of this product, add 2ml acetone to dissolve it, and add 2ml hydrochloric acid to show brown and gradually change to purplish red; Add 2ml of trichloromethane, shake fully and stand still, and the trichlorane layer will show purple blue. Weigh 5mg of this product, add 10ml of water, drop 2ml of ferric chloride, shake well, and the solution shows vermilion.
Loss on drying ≤ 6.0%;
Ignition residue ≤ 1.0%;
Components and related substances:
Erythromycin component a (dry product) ≥ 80.0%; Erythromycin B ≤ 5.0%; Erythromycin C ≤ 5.0%; Erythromycin enol ether ≤ 3.0%; Impurity 1 ≤ 3.0%; Maximum single impurity ≤ 3.0%, total impurity ≤ 5.0%.
Thiocyanate: calculated according to the dry product, the thiocyanate shall be 6.0 ~ 8.0%
Content: calculated as dry product, the titer per 1mg shall not be less than 750 erythromycin units