Fluocinolone Acetonide Topical Solution, chemical structure, molecular formula, Reference Standards

Fluocinolone Acetonide Topical Solution

»Fluocinolone Acetonide Topical Solution contains not less than 90.0percent and not more than 110.0percent of the labeled amount of C24H30F2O6.

Packaging and storage— Preserve in tight containers.

USP Reference standards á11ñ— USP Fluocinolone Acetonide RS.

Identification— Transfer a quantity of Topical Solution,equivalent to about 0.5mg of fluocinolone acetonide,to a separator,add 5mLof water,and extract with 10mLof chloroform.Withdraw the chloroform layer into a second separator,wash with 10mLof water,and dry about 2mLof the chloroform extract over about 200mg of anhydrous sodium sulfate:the dried extract responds to the Thin-Layer Chromatographic Identification Test á201ñ,50µLof the dried chloroform extract and 50µLof the Standard solution being applied,and a mixture of chloroform and diethylamine (2:1)being used for development.

Microbial limits á61ñ— It meets the requirements of the tests for absence of Staphylococcus aureusand Pseudomonas aeruginosa.

Assay—

Internal standard solution— Dissolve norethindrone in acetonitrile to obtain a solution containing about 200µg per mL.

Standard preparation— Dissolve an accurately weighed quantity of USP Fluocinolone Acetonide RSin acetonitrile to obtain a solution having a known concentration of about 200µg per mL.Transfer 5.0mLof this solution,4.0mLof Internal standard solution,10mLof propylene glycol,and about 25mLof acetonitrile to a 50-mLvolumetric flask.Mix,cool to room temperature,dilute with acetonitrile to volume,and mix.The final concentration of USP Fluocinolone Acetonide RSis 20µg per mL.

Mobile solvent— Prepare a mixture of water and acetonitrile (3:2).Adjust the ratio as necessary to obtain suitable chromatographic performance.

Assay preparation— Transfer an accurately measured volume of Topical Solution,equivalent to about 0.5mg of fluocinolone acetonide,to a 25-mLvolumetric flask.Add 2.0mLof Internal standard solutionand 10mLof acetonitrile.Mix,cool to room temperature,dilute with acetonitrile to volume,and mix.

Apparatus— Use a suitable high-pressure liquid chromatograph (see Chromatography á621ñ)of the general type equipped with a detector for monitoring UVabsorbance at about 254nm,and capable of providing a flow rate of about 2mLper minute for the Mobile solvent.Use a column containing packing L1so as to provide a resolution factor,R,of at least 2.0between peaks for norethindrone and fluocinolone acetonide.

Procedure— Chromatograph equal volumes of the Assay preparationand the Standard preparation,adjusting the system as necessary to obtain peaks of between about 50%and 90%full-scale.Calculate the quantity,in mg,of C24H30F2O6in each mLof the Topical Solution taken by the formula:

0.025(C/V)(RU/RS),

in which Cis the concentration,in µg per mL,of USP Fluocinolone Acetonide RSin the Standard preparation;Vis the volume,in mL,of Solution taken;and RUand RSare the ratios of the areas of the fluocinolone acetonide peak to the internal standard peak 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 840

Phone Number:1-301-816-8139