Diluent¡ª Prepare a mixture of water and alcohol (6:4).

Solution A¡ª Use filtered and degassed water.

Solution B¡ª Prepare a filtered and degassed mixture of acetonitrile and water (8:2).

Mobile phase¡ª Use variable mixtures of Solution Aand Solution Bas directed for Chromatographic system.Make adjustments if necessary (see System Suitabilityunder Chromatography ¨¢621ñ).

Standard solution¡ª Transfer an accurately weighed amount of USP Powdered Asian Ginseng Extract RSto a suitable volumetric flask,fill the flask with Diluentto about 60%of its nominal volume,dissolve by sonicating for 10minutes,dilute with Diluentto volume to obtain a solution having a known concentration of about 24mg per mL,mix,and filter.

Test solution¡ª Proceed as directed for Standard solution,except to use Powdered Extract.

Chromatographic system (see Chromatography ¨¢621ñ)¡ª The liquid chromatograph is equipped with a 203-nm detector,a 4.6-mm ¡Á2.0-cm guard column that contains packing L1,and a 4.6-mm ¡Á15-cm analytical column that contains 3-µmUSP28packing L1.The flow rate is about 1.5mLper minute.The column temperature is maintained at 25.USP28The chromatograph is programmed as follows.
Chromatograph the Standard solution,and record the peak areas as directed for Procedure:the chromatogram is similar to the Reference Chromatogram provided with the lot of USP Powdered Asian Ginseng Extract RSbeing used;and the relative standard deviation,determined for the sum of the peak areas for the six major ginsenosides,for replicate injections is not more than 2.0%.

Procedure¡ª Separately inject equal volumes (about 20µL)of the Standard solutionand the Test solutioninto the chromatograph,record the chromatograms,identify the peaks for the ginsenosides by comparison with the Reference Chromatogram provided with the lot of USP Powdered Asian Ginseng Extract RSbeing used,and measure the peak areas for the six major ginsenosides.Calculate the percentage of each relevant ginsenoside (Rg1,Re,Rb1,Rc,Rb2,and Rd)in the portion of Powdered Extract taken by the formula:
in which WSis the weight,in mg,of USP Powdered Asian Ginseng Extract RStaken to prepare the Standard solution;WTis the weight,in mg,of Powdered Extract taken to prepare the Test solution;rUand rSare the peak areas for each relevant ginsenoside obtained from the Test solutionand the Standard solution,respectively;and Pis the labeled amount,in percentage,of each relevant ginsenoside in USP Powdered Asian Ginseng Extract RS.Calculate the Content of ginsenosides,in percentage,by adding the percentages of each relevant ginsenoside.