Simethicone Capsules
»Simethicone Capsules contain an amount of polydimethylsiloxane ([-(CH3)2SiO-]n)that is not less than 85.0percent and not more than 115.0percent of the labeled amount of simethicone.
Packaging and storage— Preserve in well-closed containers.
Identification— Capsules respond to the Identificationtest under Simethicone.
Uniformity of dosage units á905ñ: meet the requirements.
Defoaming activity— It meets the requirements of the test for Defoaming activityunder Simethicone Oral Suspension,a quantity of Capsule contents equivalent to 20mg of simethicone being used.
Assay— [NOTE—Perform this procedure on at least 3individual Capsules.The mean of the assay values obtained is the assay value.]Transfer 1Capsule to a round,narrow-mouth,screw-capped,120-mLbottle,add about 20mLof 6Nhydrochloric acid,and allow to stand,with frequent swirling,until the Capsule has dissolved.Add 10.0mLof toluene,accurately measured,for each 25mg of the labeled amount of simethicone in the Capsule,close the bottle securely with a cap having an inert liner,and shake by mechanical means for 5minutes.Allow the phases to separate,draw off 10mLof the upper organic (toluene)layer to a test tube containing 0.5g of anhydrous sodium sulfate,agitate vigorously for 30seconds,and allow the mixture to settle.If necessary,centrifuge the mixture to obtain a clear solution (Assay preparation).Prepare a Standard preparationby similarly treating a solution of USP Polydimethylsiloxane RSin toluene having a known concentration of about 2.5mg per mL.Prepare a procedural blank by similarly treating 10.0mLof toluene.Concomitantly determine the absorbances of the solutions in 0.5-mm cells at the wavelength of maximum absorbance at about 7.9µm,with an IRspectrophotometer,using the blank to set the instrument.Calculate the quantity,in mg,of [-(CH3)2SiO-]nin the Capsule taken by the formula:
VC(AU/AS),
in which Vis the volume,in mL,of toluene taken to prepare the Assay preparation,Cis the concentration,in mg per mL,of USP Polydimethylsiloxane RSin the Standard solution,and AUand ASare the absorbances of the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Elena Gonikberg,Ph.D.,Scientist
Expert Committee:(PA4)Pharmaceutical Analysis 4
USP28–NF23Page 1769
Pharmacopeial Forum:Volume No.30(4)Page 1294
Phone Number:1-301-816-8251