Triamcinolone Acetonide Injectable Suspension »Triamcinolone Acetonide Injectable Suspension is a sterile suspension of Triamcinolone Acetonide in a suitable aqueous medium.It contains not less than 90.0percent and not more than 115.0percent of the labeled amount of C24H31FO6. Packaging and storage— Preserve in single-dose or in multiple-dose containers,preferably of Type Iglass,protected from light. USP Reference standards á11ñ USP Triamcinolone Acetonide RS.USP Endotoxin RS. Identification— Extract a volume of Injectable Suspension,equivalent to about 50mg of triamcinolone acetonide,with two 10-mLportions of peroxide-free ether,and discard the ether extracts.Filter with the aid of suction,wash with small portions of water,and dry the precipitate at 105for 1hour:the triamcinolone acetonide so obtained responds to the Identificationtests under Triamcinolone Acetonide. Bacterial endotoxins á85ñ It contains not more than 4.4USP Endotoxin Units per mg of triamcinolone acetonide. pHá791ñ: between 5.0and 7.5. Other requirements— It meets the requirements under Injections á1ñ. Assay— Mobile phase: approximately 30%acetonitrile in water. Internal standard solution— Dissolve fluoxymesterone in methanol to obtain a solution having a concentration of about 84µg per mL. Standard preparation— Dissolve an accurately weighed quantity of USP Triamcinolone Acetonide RSin methanol to obtain a solution having a known concentration of about 200µg per mL.Pipet 20mLof this solution into a 50-mLvolumetric flask,dilute with Internal standard solutionto volume,and mix.The Standard preparationhas a known concentration of about 80µg of USP Triamcinolone Acetonide RSper mL. Assay preparation— Dissolve an accurately measured volume of freshly mixed Injectable Suspension in methanol,and dilute quantitatively with methanol to obtain a solution having an expected concentration of about 200µg of triamcinolone acetonide per mL.Pipet 20mLof this solution into a 50-mLvolumetric flask,dilute with Internal standard solutionto volume,and mix. Procedure— Proceed as directed for Procedurein the Assayunder Triamcinolone Acetonide Cream,except to use peak responses in the calculation.Calculate the quantity,in mg,of C24H31FO6in each mLof the Injectable Suspension taken by the formula: (CD/V)(RU/RS), in which Cis the concentration,in mg per mL,of USP Triamcinolone Acetonide RSin the Standard preparation,Dis the dilution factor used in the Assay preparation,Vis the volume,in mL,of Injectable Suspension taken,and RUand RSare the ratios of the peak responses of triamcinolone acetonide to the internal standard,obtained from the Assay preparationand the Standard preparation,respectively. Auxiliary Information— Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist Expert Committee:(PA1)Pharmaceutical Analysis 1 USP28–NF23Page 1961 Phone Number:1-301-816-8139