Determine the amount of C17H19NO3·HCl dissolved by employing the following method.

Test solution— Withdraw a 15-mLportion of the solution under test,filter,and discard the first few mLof the filtrate.

Standard solution— Dissolve an accurately weighed quantity of USP Hydromorphone Hydrochloride RSin water at a concentration similar to that of the Test solution.

Chromatographic system— Proceed as directed in the Assay,except to inject the Standard solutioninstead of the Standard preparationto obtain the relative standard deviation for replicate injections of not more than 5.0%.

Procedure— Proceed as directed in the Assay,except to use an injection volume of about 200µL.

Mobile phase— Prepare a filtered and degassed mixture of Buffer solutionand acetonitrile (33:17).Make adjustments if necessary.

System suitability solution— Dissolve suitable quantities of USP Morphine Sulfate RSand USP Hydromorphone Hydrochloride RSin water to obtain a solution containing about 30and 40µg of each per mL,respectively.

Standard preparation— Dissolve an accurately weighed quantity of USP Hydromorphone Hydrochloride RSin water,and dilute quantitatively,and stepwise if necessary,with water to obtain a solution having a known concentration of about 40µg per mL.

Assay preparation— Weigh and finely powder not fewer than 20Tablets.Transfer a portion of the powder,equivalent to about 4mg of hydromorphone hydrochloride,to a 100-mLvolumetric flask,dissolve in and dilute with water to volume,sonicate if necessary,and mix.Filter a portion of the solution using a glass fiber filter,and discard the first 5mL.

Chromatographic system (see Chromatography á621ñ)— The liquid chromatograph is equipped with a 280-nm detector and a 4.6-mm ×15-cm column that contains packing L1.The flow rate is about 1.5mLper minute.Chromatograph the System suitability solution,and record the peak responses as directed for Procedure:the resolution,R,between morphine and hydromorphone is not less than 2.0.Chromatograph the Standard preparation,and record the peak responses as directed for Procedure:the tailing factor for the hydromorphone hydrochloride peak is not more than 2.0;and the relative standard deviation for replicate injections is not more than 3.0%.

Procedure— Separately inject equal volumes (about 100µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of hydromorphone hydrochloride (C17H19NO3·HCl)in the portion of Tablets taken by the formula: in which Cis the concentration,in µg per mL,of USP Hydromorphone Hydrochloride RSin the Standard preparation;and rUand rSare the peak responses obtained from the Assay preparationand the Standard preparation,respectively.