A: The retention time of the major peak in the chromatogram of theAssay preparation corresponds to that in the chromatogram of theStandard preparation,as obtained in theAssay.

B: It meets the requirements of the test for Specific rotation á781Sñ.

C: Mix 0.2g with 2mLof iodine TS,warm in a water bath to dissolve the test specimen,and allow to stand at room temperature:a yellow-brown precipitate is formed.

Test solution: 10mg per mL,in water.

Potassium chloride solution— Transfer 22.4g of potassium chloride into a 100-mLvolumetric flask,and dilute with water to volume.

Cupric solution— Dissolve 15g of cupric sulfate in water to make 100mL.

Tartrate solution— Dissolve 2.5g of anhydrous sodium carbonate,2.5g of potassium sodium tartrate,2.0g of sodium bicarbonate,and 20g of anhydrous sodium sulfate in water to make 100mL.

Cupric–tartaric solution— Immediately before use,mix 1part ofCupric solution with 25parts ofTartrate solution.

Ammonium molybdate reagent— Mix 10mLof a solution of disodium arsenate (6in 100),50mLof a solution of ammonium molybdate (1in 10),and 90mLof diluted sulfuric acid,and dilute with water to 200mL.

Test solution— Transfer about 1.0g of Alfadex,accurately weighed,to a 100-mLvolumetric flask,dissolve in and dilute with water that has been previously boiled and cooled to room temperature,to volume,and mix.To 1mLof this solution add 1mLofCupric–tartaric solution.Heat on a water bath for 10minutes,then cool to room temperature.Add 10mLofAmmonium molybdate reagent,and allow to stand for 15minutes.

Standard solution— Prepare as directed for the Test Solution,at the same time,except to use 1mLof a solution containing 20mg of glucose per L.

Procedure— Concomitantly measure the absorbance of theTest solution and theStandard solution at the wavelength of maximum absorbance at 740nm relative to that of water,with a suitable spectrophotometer.The absorbance of theTest solution is not greater than that of theStandard solution (0.2%).

System suitability solution— Prepare as directed for System suitability preparationin the Assay.

Standard solution— Transfer 5.0mLof theSystem suitability solution into a 50-mLvolumetric flask,and dilute with water to volume.

Test solution— Use theAssay stock preparation prepared as directed in theAssay.

Chromatographic system(see Chromatography á621ñ)— Proceed as directed in the Assay.

Procedure— Separately inject equal volumes (about 50µL)of theStandard solution and theTest solution into the chromatograph,record the chromatograms,and measure the responses for the major peaks.For theTest solution,the areas of any peaks corresponding to beta cyclodextrin or to gamma cyclodextrin are not greater than half of the area of the corresponding peaks in the chromatogram of theStandard solution (0.25%),and the sum of the areas of all the peaks,excluding the principal peak and the peaks corresponding to beta cyclodextrin or to gamma cyclodextrin,is not greater than half of the area of the peak corresponding to alpha cyclodextrin in the chromatogram of theStandard solution (0.5%).

Test solution— Transfer about 1.0g of Alfadex,accurately weighed,to a 100-mLvolumetric flask,dissolve in and dilute with water,which has been previously boiled and cooled to room temperature,to volume,and mix.

Procedure— Determine the absorbance of theTest solution in a 1-cm cell with a suitable spectrophotometer,after correcting for the blank:between 230nm and 350nm,the absorbance is not greater than 0.10;and between 350nm and 750nm,the absorbance is not greater than 0.05.

Mobile phase— Prepare a filtered and degassed mixture of water and methanol (90:10).Make adjustments if necessary (seeSystem Suitability underChromatography á621ñ).

Standard preparation— Transfer 25mg of USP Alpha Cyclodextrin RS,accurately weighed,to a 25-mLvolumetric flask,and dissolve in and dilute with water to volume.

System suitability preparation— Transfer 25mg of USP Beta Cyclodextrin RS,25mg of USP Gamma Cyclodextrin RS,and 50mg of USP Alpha Cyclodextrin RS,accurately weighed,to a 50-mLvolumetric flask,dissolve in and dilute with water to volume,and mix.

Assay stock preparation— Transfer 250mg of Alfadex,accurately weighed,to a 25-mLvolumetric flask,and dissolve in water with the aid of heat.Cool,and dilute with water to volume.

Assay preparation— Transfer 5.0mLof theAssay stock preparation to a 50-mLvolumetric flask,and dilute with water to volume.

Chromatographic system(see Chromatography á621ñ)— The liquid chromatograph is equipped with a refractive index detector and a 4.6-mm ×25-cm column that contains 10-µm packing L1.The flow rate is about 1.5mLper minute.Chromatograph theSystem suitability preparation,and record the chromatograms for about 3.5times the retention time of alpha cyclodextrin.Record the peak responses as directed forProcedure:the retention time of alpha cyclodextrin is about 4.5minutes;the relative retention times are about 1.0for alpha cyclodextrin,about 2.2for beta cyclodextrin,and about 0.7for gamma cyclodextrin;the resolution,R,between the gamma cyclodextrin and alpha cyclodextrin peaks is not less than 1.5;and for the alpha cyclodextrin peak,the relative standard deviation for replicate injections is not more than 2.0%.

Procedure— Separately inject equal volumes (about 50µL)of theStandard preparation and theAssay preparation into the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the percentage of (C6H10O5)6in the portion of Alfadex taken by the formula: in whichCis the concentration,in mg per mL,of alpha cyclodextrin in theStandard preparation,calculated on the dried basis,as determined from the concentration of USP Alpha Cyclodextrin RScorrected for the declared moisture content;Wis the weight,in mg,of alpha cyclodextrin taken to prepare theAssay stock preparation;andRUandRSare the peak responses of the alpha cyclodextrin peak obtained from theAssay preparation and theStandard preparation,respectively.NF23