Dexamethasone Acetate Injectable Suspension
»Dexamethasone Acetate Injectable Suspension is a sterile suspension of Dexamethasone Acetate in Water for Injection.It contains an amount of dexamethasone acetate monohydrate (C24H31FO6·H2O)equivalent to not less than 90.0percent and not more than 110.0percent of the labeled amount of dexamethasone (C22H29FO5).
Packaging and storage— Preserve in single-dose or in multiple-dose containers,preferably of Type Iglass.
Identification,Infrared Absorption á197Mñ— Obtain the test specimen as follows.Transfer the contents of a well-shaken container of Injectable Suspension to a fine-porosity,sintered-glass vacuum filter,filter,and wash with several 10-mLportions of water.Remove the powder from the filter and allow to air-dry.[NOTE—Do not use heat to dry the specimen.Total or partial dehydration may occur.Use a similar undried preparation of USP Dexamethasone Acetate RS.]
Bacterial endotoxins á85ñ— It contains not more than 21.7USP Endotoxin Units per mg of dexamethasone acetate.
pHá791ñ: between 5.0and 7.5.
Other requirements— It meets the requirements under Injections á1ñ.
Assay—
Mobile phase,pH6.0Buffer solution,Diluent,and Chromatographic system— Proceed as directed in the Assayunder Dexamethasone Acetate.
Standard preparation— Dissolve an accurately weighed quantity of USP Dexamethasone Acetate RSin Diluentto obtain a solution having a known concentration of about 0.09mg per mL.
Assay preparation— Transfer an accurately measured volume of well-shaken Injectable Suspension,equivalent to about 40mg of dexamethasone,to a 100-mLvolumetric flask.Add 75mLof Diluent,and sonicate until a clear solution is obtained.Dilute with Diluentto volume,and mix.Transfer 10.0mLof this solution to a 50-mLvolumetric flask,dilute with Diluentto volume,and mix.
Procedure— Separately inject equal volumes (about 20µL)of the Standard preparation(before and after injections of the Assay preparation)and the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of dexamethasone (C22H29FO5)in each mLof the Injectable Suspension taken by the formula:
(392.47/434.51)(500C/V)(rU/rS),
in which 392.47and 434.51are the molecular weights of dexamethasone and anhydrous dexamethasone acetate,respectively;Cis the concentration,in mg per mL,of USP Dexamethasone Acetate RSin the Standard preparation;Vis the volume,in mL,of Injectable Suspension taken;and rUandrSare the peak responses 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 592
Phone Number:1-301-816-8139