Tetracycline Hydrochloride,Novobiocin Sodium,and Prednisolone Tablets »Tetracycline Hydrochloride,Novobiocin Sodium,and Prednisolone Tablets contain not less than 90.0percent and not more than 125.0percent of the labeled amounts of tetracycline hydrochloride (C22H24N2O8·HCl)and novobiocin (C31H36N2O11),and not less than 90.0percent and not more than 110.0percent of the labeled amount of prednisolone (C21H28O5). Packaging and storage— Preserve in tight containers. Labeling— Label the Tablets to indicate that they are intended for veterinary use only. USP Reference standards á11ñ USP Tetracycline Hydrochloride RS.USP Novobiocin RS.USP Prednisolone RS. Disintegration á701ñ: 60minutes,simulated gastric fluid TSbeing substituted for water in the test. Uniformity of dosage units á905ñ: meet the requirements for Weight Variationwith respect to tetracycline hydrochloride and to novobiocin sodium and for Content Uniformitywith respect to prednisolone. Procedure for content uniformity for prednisolone— Mobile phase ,Internal standard solution,and Chromatographic system—Prepare as directed in the Assayunder Prednisolone. Standard preparation— Prepare as directed in the Assay for prednisolone. Test preparation— Transfer 1Tablet to a suitable container,add 7mLof diluted methanol (2in 7)for each 1.5mg of prednisolone in the Tablet,based on the labeled amount,and allow to stand for 90minutes,occasionally agitating gently to ensure that the Tablet disintegrates.For each 1.5mg of prednisolone,add 3.0mLof Internal standard solution,12mLof water-saturated chloroform,and about 10glass beads.Securely close the container,and shake by mechanical means for 30minutes.Carefully open the container,add 0.5mLof sodium carbonate solution (1in 4),reclose the container,and shake by mechanical means for 5minutes.Centrifuge,remove the upper layer by aspiration,discarding the aspirated liquid,and retain the clear chloroform layer (Test preparation). Procedure— Proceed as directed for Procedurein the Assayunder Prednisolone.Calculate the quantity,in mg,of prednisolone (C21H28O5)in the Tablet taken by the formula: 0.015C(RU/RS), in which the terms are as defined therein. Limit of 4-epianhydrotetracycline á226ñ To an accurately weighed quantity of finely powdered Tablets,equivalent to about 250mg of tetracycline hydrochloride,add 10mLof 0.1Nhydrochloric acid,and adjust with 6Nammonium hydroxide to a pHof 7.8.Transfer this solution with the aid of EDTA Bufferto a 50-mLvolumetric flask,dilute with EDTA Bufferto volume,and mix.Use this solution,without delay,as the Test Solution:not more than 2.0%is found. Other requirements— Tablets respond to the Identificationtest and meet the requirements of the test for Loss on dryingunder Tetracycline Hydrochloride and Novobiocin Sodium Tablets. Assay for tetracycline hydrochloride and Assay for novobiocin— Using Tablets,proceed as directed in the Assay for tetracycline hydrochlorideand the Assay for novobiocinunder Tetracycline Hydrochloride and Novobiocin Sodium Tablets. Assay for prednisolone— Mobile phase ,Internal standard solution,and Chromatographic system—Prepare as directed in the Assayunder Prednisolone. Standard preparation— Transfer about 10mg of USP Prednisolone RS,accurately weighed,to a 100-mLvolumetric flask,add 20.0mLof Internal standard solution,and swirl to dissolve.Dilute with water-saturated chloroform to volume,and mix.Transfer 15.0mLof this solution to a suitable container,add 7mLof diluted methanol (2in 7),securely close the container,and shake by mechanical means for 30minutes.Carefully open the container,add 0.5mLof sodium carbonate solution (1in 4),reclose the container,and shake by mechanical means for 5minutes.Centrifuge,remove the upper layer by aspiration,discarding the aspirated liquid,and retain the clear chloroform layer (Standard preparation). Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 1.5mg of prednisolone,to a suitable container containing about 10glass beads.Add 3.0mLof Internal standard solution,12mLof water-saturated chloroform,and 7mLof diluted methanol (2in 7),securely close the container,and shake by mechanical means for 30minutes.Carefully open the container,add 0.5mLof sodium carbonate solution (1in 4),reclose the container,and shake by mechanical means for 5minutes.Centrifuge,remove the upper layer by aspiration,discarding the aspirated liquid,and retain the clear chloroform layer (Assay preparation). Procedure— Proceed as directed for Procedurein the Assayunder Prednisolone.Calculate the quantity,in mg,of prednisolone (C21H28O5)in the portion of Tablets taken by the formula: 0.015C(RU/RS), in which the terms are as defined therein. Auxiliary Information— Staff Liaison:Ian DeVeau,Ph.D.,Senior Scientist Expert Committee:(VET)Veterinary Drugs USP28–NF23Page 1891 Phone Number:1-301-816-8178