Chlordiazepoxide Hydrochloride and Clidinium Bromide Capsules
»Chlordiazepoxide Hydrochloride and Clidinium Bromide Capsules contain not less than 90.0percent and not more than 110.0percent of the labeled amounts of chlordiazepoxide hydrochloride (C16H14ClN3O·HCl)and clidinium bromide (C22H26BrNO3).
Packaging and storage— Preserve in tight,light-resistant containers.
Identification— The retention times of the major peaks in the chromatogram of the Assay preparationcorrespond to those of the Standard preparationas obtained in the Assay.
Dissolution,Procedure for a Pooled Sample á711ñ—
Medium: water;900mL.
Apparatus 1: 100rpm.
Time: 30minutes.
Determine the amounts of chlordiazepoxide hydrochloride and clidinium bromide dissolved using the following method.
Solution A— Dissolve 1.92g of sodium 1-pentanesulfonate in 900mLof water.Adjust the solution with dilute sulfuric acid (1in 100)to a pHof 3.8±0.1,dilute with water to 1.0liter,and mix.
Mobile phase— Prepare a filtered and degassed mixture of Solution A,tetrahydrofuran,and methanol (75:18:6).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Chromatographic system— The liquid chromatograph is equipped with a 212-nm detector and a 4-mm ×25-cm column that contains packing L1.The flow rate is about 2mLper minute.Chromatograph replicate injections of the Standard solution,and record the peak responses as directed for Procedure:the resolution between the two components is not less than 5.0,and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure— Separately inject equal volumes (about 100µL)of a Standard solution and a filtered portion of the solution under test into the chromatograph,record the chromatograms,and measure the responses for the major peaks.The relative retention times are about 0.6for clidinium bromide and 1.0for chlordiazepoxide hydrochloride.Calculate the amounts of chlordiazepoxide hydrochloride (C16H14ClN3O·HCl)and clidinium bromide (C22H26BrNO3)dissolved in comparison with a Standard solution having known concentrations of USP Chlordiazepoxide Hydrochloride RSand USP Clidinium Bromide RS,similarly prepared and chromatographed.
Tolerances— Not less than 75%(Q)each of the labeled amounts of C16H14ClN3O·HCl and C22H26BrNO3are dissolved in 30minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Related compounds—
A:LIMITOF CHLORDIAZEPOXIDE RELATED COMPOUNDAAND2-AMINO-5-CHLOROBENZOPHENONE— Proceed with the Capsules as directed in the test for Related compoundsunder Chlordiazepoxide Hydrochloride Capsules.Not more than 3.0%of chlordiazepoxide related compound Ais found;and not more than 0.1%of 2-amino-5-chlorobenzophenone is found.
B:LIMITOF3-QUINUCLINDINYL BENZILATE—
Adsorbent: 0.25-mm layer of chromatographic silica gel mixture.
Test solution— Place a glass wool plug in the bottom of a 2.5-cm ×35±5-cm glass chromatographic tube,add 2g of chromatographic siliceous earth triturated with 1mLof 1Nhydrochloric acid,and lightly pack with a glass tamping rod.Empty a number of Capsules,equivalent to about 15mg of clidinium bromide,into a 100-mLbeaker,add 3mLof 1Nhydrochloric acid,and swirl to dissolve.Add 4g of chromatographic siliceous earth,mix with a spatula,and add the Capsule-siliceous earth mixture to the chromatographic tube.Dry-wash the beaker with an additional 0.5to 1.0g of chromatographic siliceous earth,adding the washing to the top of the column.Lightly pack with the tamping rod,and overlay the column with glass wool.Insert the lower exit tube of the column into a 125-mLseparator,and elute the column with 100mLof chloroform previously distilled over 1Nsulfuric acid and saturated with water.Extract the chloroform eluate with 20mLof freshly prepared ascorbic acid solution (1in 20),preserving the extract.Extract the eluate with a second 15-mLportion of the ascorbic acid solution,combine the extracts in the separator,and discard the chloroform layer.Neutralize the acid extracts by adding sodium bicarbonate until the solution is slightly alkaline to the pHpaper.Extract the slightly alkaline solution with two 25-mLportions of chloroform,combine the chloroform extracts,and pass through dry,fluted filter paper into a 100-mLbeaker.Evaporate the chloroform to dryness with the aid of a stream of nitrogen,and transfer the residue to a glass-stoppered 1.0-mLvolumetric flask,using methanol to facilitate the transfer.Dilute with methanol to volume.
Reference solution— Dissolve 3.0mg of USP3-Quinuclidinyl Benzilate RSin 100mLof methanol,and mix.
Developing solvent system: methanol.
Procedure— Separately apply 15µLof the Reference solutionand 100µLof the Test solutionto a suitable chromatographic plate,place the plate in a paper-lined,methanol-saturated chromatographic chamber,and proceed as directed for Thin-layer Chromatographyunder Chromatography á621ñ.Remove the plate,air-dry,spray with potassium iodoplatinate TS,and allow the spots to develop for 10minutes.Any spot in the chromatogram obtained from the Test solutionoccurring at an RFvalue of about 0.3is not greater in size or intensity than the spot in the chromatogram obtained from the Reference solution:not more than 0.03%of 3-quinuclidinyl benzilate is found.
C:LIMITOFCLIDINIUM BROMIDE RELATED COMPOUND A—
Adsorbent,Developing solvent system,Chromatographic plates,and Spray reagent— Prepare as directed in the test for Related compoundsunder Clidinium Bromide.
Extracting solvent mixture: a mixture of dehydrated alcohol and cyclohexane (1:1).
Test solution— Empty a number of Capsules,equivalent to about 25mg of clidinium bromide,into a glass-stoppered centrifuge tube,and add 5mLof Extracting solvent mixture.Heat the tube gently,with shaking,to 50,centrifuge,and decant the clear supernatant into a second tube.Repeat the addition of Extracting solvent mixturetwice,heating,centrifuging,and decanting as before,and combine the three extracts in a single tube.Gently heating,evaporate the combined extracts under a stream of nitrogen to dryness.Dissolve the residue in 0.5mLof methanol.
Standard solution— Dissolve 50mg of USP Clidinium Bromide RSin 1.0mLof 0.1Nmethanolic hydrochloric acid.Prepare this solution at the time of use.
Reference solution— Dissolve 50mg of USP Clidinium Bromide RSin 1.0mLof 0.1Nmethanolic hydrochloric acid,and add 20µLof a solution of 25mg of USP Clidinium Bromide Related Compound A RSin 1.0mLof methanol.Prepare this solution at the time of use.
Application volume: 20µL.
Procedure— Separately apply the Standard solution,the Reference solution,and the Test solutionas directed in Thin-Layer Chromatographyunder Chromatography á621ñ.Place the plates in an unsaturated chromatographic chamber containing freshly prepared Developing solvent system,and develop the chromatogram until the solvent front has moved about 15cm.Remove the plates,and dry at 105for 10minutes.Cool to room temperature,and spray with Spray reagent.Any spot in the chromatogram obtained from the Test solutionoccurring at an RFvalue of about 0.4is not greater in size or intensity than the corresponding spot in the chromatogram obtained from the Reference solution;and the Standard solutionshows no spot at the RFvalue corresponding to that of clidinium bromide related compound A:not more than 1.0%of clidinium bromide related compound Ais found.
Assay— [NOTE—Use low-actinic glassware in this procedure.]
Sodium 1-pentanesulfonate solution— Dissolve 1.92g of sodium 1-pentanesulfonate in about 900mLof water in a 1-liter volumetric flask.Adjust with 1Nsulfuric acid to a pHof 3.8±0.1,dilute with water to volume,mix,and filter.
Mobile phase— Prepare a filtered and degassed mixture of Sodium 1-pentanesulfonate solution,tetrahydrofuran,and methanol (70:24:6).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).
Solvent mixture— Prepare a mixture of water and methanol (1:1).
Standard preparation— Dissolve accurately weighed quantities of USP Chlordiazepoxide Hydrochloride RSand USP Clidinium Bromide RSin Solvent mixture,and dilute quantitatively,and stepwise if necessary,with Solvent mixtureto obtain a solution having known concentrations of about 0.1mg of USP Chlordiazepoxide Hydrochloride RSand 0.05mg of USP Clidinium Bromide RSper mL.
Assay preparation— Weigh the contents of not less than 20Capsules,and calculate the average weight per Capsule.Mix the combined contents of the Capsules,and transfer an accurately weighed portion,equivalent to about 5mg of chlordiazepoxide hydrochloride (C16H14ClN3O·HCl),to a 50-mLvolumetric flask.Add about 25mLof Solvent mixture,sonicate for 5minutes,and shake by mechanical means for 10minutes.Dilute with Solvent mixtureto volume,mix,and filter,discarding the first 20mLof the filtrate.
Chromatographic system (see Chromatography á621ñ)— The liquid chromatograph is equipped with a 212-nm detector and an 8-mm ×100-mm column that contains packing L1.The flow rate is about 3mLper minute.Chromatograph the Standard preparation,and record the peak responses as directed for Procedure:the resolution,R,between the clidinium bromide and chlordiazepoxide hydrochloride peaks is not less than 5.0,and the relative standard deviation for replicate injections is not more than 2.0%.The relative retention times are about 0.5for clidinium bromide and 1.0for chlordiazepoxide hydrochloride.
Procedure— Separately inject equal volumes (about 20µL)of the Assay preparationand the Standard preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of chlordiazepoxide hydrochloride (C16H14ClN3O·HCl)in the portion of Capsules taken by the formula:
50C(rU/rS),
in which Cis the concentration,in mg per mL,of USP Chlordiazepoxide Hydrochloride RSin the Standard preparation,and rUand rSare the chlordiazepoxide hydrochloride peak responses obtained from the Assay preparationand the Standard preparation,respectively.Calculate the quantity,in mg,of clidinium bromide (C22H26BrNO3)in the portion of Capsules taken by the same formula,reading clidinium bromide instead of chlordiazepoxide hydrochloride.
Auxiliary Information— Staff Liaison:Ravi Ravichandran,Ph.D.,Senior Scientist
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 438
Pharmacopeial Forum:Volume No.30(1)Page 83
Phone Number:1-301-816-8330