Chlortetracycline and Sulfamethazine Bisulfates Soluble Powder
»Chlortetracycline and Sulfamethazine Bisulfates Soluble Powder is a dry mixture of Chlortetracycline Bisulfate and Sulfamethazine Bisulfate and one or more suitable buffers and diluents.It contains the equivalent of not less than 85.0percent and not more than 125.0percent of the labeled amounts of chlortetracycline hydrochloride (C22H24N2O8·HCl)and sulfamethazine (C12H14N4O2S).
Packaging and storage— Preserve in tight,light-resistant containers.
Labeling— Label it to indicate that it is intended for veterinary use only.
Loss on drying á731ñ— Dry about 100mg,accurately weighed,in a capillary-stoppered bottle in vacuum at a pressure not exceeding 5mm of mercury at 60for 3hours:it loses not more than 2.0%of its weight.
Assay for chlortetracycline hydrochloride— Proceed as directed for chlortetracycline under Antibiotics—Microbial Assays á81ñ,using an accurately weighed quantity of Powder,equivalent to about 100mg of chlortetracycline hydrochloride,dissolved in an accurately measured volume of 0.01Nhydrochloric acid to obtain a stock solution having a convenient concentration.Dilute an accurately measured volume of this stock solution quantitatively and stepwise with water to obtain a Test Dilutionhaving a concentration assumed to be equal to the median dose level of the Standard.
Assay for sulfamethazine— Proceed as directed under Nitrite Titration á451ñ,using an accurately weighed quantity of Powder,equivalent to about 500mg of sulfamethazine.Each mLof 0.1Msodium nitrite is equivalent to 27.83mg of sulfamethazine (C12H14N4O2S).
Auxiliary Information— Staff Liaison:Ian DeVeau,Ph.D.,Senior Scientist
Expert Committee:(VET)Veterinary Drugs
USP28–NF23Page 459
Phone Number:1-301-816-8178