Determine the amounts of chlordiazepoxide hydrochloride and clidinium bromide dissolved using the following method.

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.

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.

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.

50C(rU/rS),