Halcinonide Cream
»Halcinonide Cream is Halcinonide in a suitable cream base.It contains not less than 90.0percent and not more than 110.0percent of the labeled amount of C24H32ClFO5.
Packaging and storage—
Preserve in well-closed containers.
Identification—
Transfer a quantity of Cream,equivalent to about 2mg of halcinonide,to a glass-stoppered,50-mLcentrifuge tube,add 15mLof warm water,and shake for 2minutes to disperse.Add 20mLof chloroform,and shake for 5minutes.Cool in an ice bath,then centrifuge.Transfer the chloroform layer to a conical flask.Repeat the extraction with an additional 15mLof chloroform,and combine the chloroform extracts.Evaporate the chloroform extracts on a steam bath under a current of air nearly to dryness,and dissolve the residue in 10.0mLof chloroform.Apply 20µLof this solution and 20µLof a solution of USP Halcinonide RSin chloroform having a concentration of 0.2mg per mLto a thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture.Develop the chromatogram in a solvent system consisting of a mixture of chloroform and ethyl acetate (5:1)until the solvent front has moved about three-fourths of the length of the plate.Remove the plate,air-dry,and view the chromatogram under short-wavelength UVlight:the RFvalue of the principal spot obtained from the test solution corresponds to that obtained from the Standard solution.
Microbial limits á61ñ—
It meets the requirements of the tests for absence of Staphylococcus aureusand Pseudomonas aeruginosa.
Minimum fill á755ñ:
meets the requirements.
Assay—
Solvent A—
On the day of use,prepare a mixture of acetonitrile and water (2:1).
Mobile phase—
Mix approximately equal volumes of acetonitrile and water,adjusting the composition as necessary to achieve acceptable chromatography.
Internal standard solution—
Transfer 15mg of Progesterone to a 100-mLvolumetric flask.Dissolve in hexanes-saturated Solvent A,dilute with hexanes-saturated Solvent Ato volume,and mix.
Standard preparation—
Transfer about 20mg of USP Halcinonide RS,accurately weighed,to a 100-mLvolumetric flask,dissolve in Solvent A,dilute with Solvent Ato volume,and mix.Transfer 5.0mLof this solution to a 50-mLvolumetric flask.Add 4.0mLof Internal standard solution,dilute with hexanes-saturated Solvent Ato volume,and mix.
Assay preparation—
Transfer an accurately weighed quantity of Cream,equivalent to about 0.5mg of halcinonide,to a glass-stoppered,50-mLcentrifuge tube,add 12mLof hexanes-saturated Solvent Aand 20mLof hexanes,and shake for 1minute.Place in a heated ultrasonic bath at 58±2
for 20minutes,initially shaking for 1to 2minutes to ensure dispersion,and at about 5-minute intervals thereafter,on a vibratory mixer.Cool,centrifuge,and transfer the lower layer to a 25-mLvolumetric flask.Add 5mLof hexanes-saturated Solvent Ato the tube,mix for 1minute,then centrifuge.Transfer the lower layer to the volumetric flask,and repeat the extraction with an additional 5mLof hexanes-saturated Solvent A,combining the extracts in the flask.Add 2.0mLof Internal standard solutionto the flask,dilute with hexanes-saturated Solvent Ato volume,and mix.If necessary,clarify a portion of the solution by centrifugation.
for 20minutes,initially shaking for 1to 2minutes to ensure dispersion,and at about 5-minute intervals thereafter,on a vibratory mixer.Cool,centrifuge,and transfer the lower layer to a 25-mLvolumetric flask.Add 5mLof hexanes-saturated Solvent Ato the tube,mix for 1minute,then centrifuge.Transfer the lower layer to the volumetric flask,and repeat the extraction with an additional 5mLof hexanes-saturated Solvent A,combining the extracts in the flask.Add 2.0mLof Internal standard solutionto the flask,dilute with hexanes-saturated Solvent Ato volume,and mix.If necessary,clarify a portion of the solution by centrifugation.
Chromatographic system
(see Chromatography á621ñ)—The liquid chromatograph is equipped with a 254-nm detector and a 4-mm ×30-cm column that contains packing L1.The flow rate is about 2mLper minute.Chromatograph the Standard preparation,and record the peak responses as directed under Procedure:the resolution,R,between the analyte and internal standard peaks is not less than 1.5,and the relative standard deviation for replicate injections is not more than 3.0%.
Procedure—
Separately inject equal volumes (about 20µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.The relative retention times are about 1.2for progesterone and 1.0for halcinonide.Calculate the quantity,in mg,of C24H32ClFO5in the portion of Cream taken by the formula:
25C(RU/RS),
in which Cis the concentration,in mg per mL,of USP Halcinonide RSin the Standard preparation,and RUand RSare the ratios of the peak responses of halcinonide to internal standard obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information—
Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist
Expert Committee:(PA2)Pharmaceutical Analysis 2
USP28–NF23Page 936
Phone Number:1-301-816-8139