TEST1
Buffer solution
Prepare as directed in theAssay.
Mobile phase
Prepare a filtered and degassed mixture of
Buffer solutionand methanol (56:44).Make adjustments if necessary (see
System Suitabilityunder
Chromatography á621ñ).
Diluent
Prepare a mixture of Buffer solutionand methanol (50:50).
Standard solution
Transfer about 30mg of
USP Acebutolol Hydrochloride RS,accurately weighed,to a 50-mLvolumetric flask.Add about 12mLof methanol,swirl to dissolve,dilute with
Diluentto volume,and mix.Dilute an accurately measured volume of this solution quantitatively,and stepwise if necessary,with
Diluentto obtain a solution having a known concentration of about 1.4µg of
USP Acebutolol Hydrochloride RSper mL.
Test solution
Transfer an accurately weighed portion of the contents of 20opened Capsules,equivalent to about 250mg of acebutolol,to a 100-mLvolumetric flask,add about 25mLof methanol,and shake by mechanical means for about 15minutes.Dilute withDiluentto volume,and mix.Centrifuge a portion of this solution,and transfer 10.0mLof the clear supernatant to a 100-mLvolumetric flask.Dilute withDiluentto volume,and mix.
Chromatographic system(see Chromatography á621ñ)
The liquid chromatograph is equipped with a 240-nm detector and a 3.9-mm ×15-cm column that contains 4-µm packing L1.The flow rate is about 1mLper minute.Chromatograph the
Standard solution,and record the peak responses as directed for
Procedure:the relative standard deviation for replicate injections is not more than 6.0%.
Procedure
Separately inject equal volumes (about 35µL)of the
Standard solution,Test solution,and
Diluentinto the chromatograph,record the chromatograms for about two times the retention time of acebutolol,and measure the responses for all the peaks,disregarding any peaks corresponding to those obtained from the
Diluent.Calculate the percentage of each impurity eluting prior to the acebutolol peak in the portion of Capsules taken by the formula:
(336.44/372.89)(0.4C)(ri/rS),
in which 336.44and 372.89are the molecular weights of acebutolol and acebutolol hydrochloride,respectively;
Cis the concentration,in µg per mL,of
USP Acebutolol Hydrochloride RSin the
Standard solution;riis the peak response of any individual impurity obtained from the
Test solution;and
rSis the peak response of acebutolol obtained from the
Standard solution:not more than 0.5%of any individual impurity is found.
TEST2
Buffer solution
Prepare as directed in theAssay.
Mobile phase
Prepare a filtered and degassed mixture of
Buffer solutionand methanol (50:50).Make adjustments if necessary (see
System Suitability under
Chromatography á621ñ).
Standard solution
Transfer about 30mg of
USP Acebutolol Hydrochloride RS,accurately weighed,to a 50-mLvolumetric flask.Add about 12mLof methanol,swirl to dissolve,dilute with
Mobile phaseto volume,and mix.Dilute an accurately measured volume of this stock solution quantitatively,and stepwise if necessary,with
Mobile phaseto obtain a solution having a known concentration of about 1.4µg of
USP Acebutolol Hydrochloride RSper mL.
Test solution
Transfer an accurately weighed portion of the contents of 20opened Capsules,equivalent to about 250mg of acebutolol,to a 100-mLvolumetric flask,add about 25mLof methanol,and shake by mechanical means for about 15minutes.Dilute withMobile phaseto volume,and mix.Centrifuge a portion of this solution,and transfer 10.0mLof the clear supernatant to a 100-mLvolumetric flask.Dilute withMobile phaseto volume,and mix.
Chromatographic system(see Chromatography á621ñ)
The liquid chromatograph is equipped with a 240-nm detector and a 3.9-mm ×15-cm column that contains 4-µm packing L1.The flow rate is about 1mLper minute.Chromatograph the
Standard solution,and record the peak responses as directed for
Procedure:the relative standard deviation for replicate injections is not more than 6.0%.
Procedure
Separately inject equal volumes (about 70µL)of the
Standard solution,Test solution,and
Mobile phaseinto the chromatograph,record the chromatograms for about three times the retention time of acebutolol,and measure the responses for all the peaks,disregarding any peaks corresponding to those obtained from the
Mobile phase.Calculate the percentage of each impurity eluting after the acebutolol peak in the portion of Capsules taken by the formula:
(336.44/372.89)(0.4C)(ri/rS),
in which 336.44and 372.89are the molecular weights of acebutolol and acebutolol hydrochloride,respectively;
Cis the concentration,in µg per mL,of
USP Acebutolol Hydrochloride RSin the
Standard solution;riis the peak response of any individual impurity obtained from the
Test solution;and
rSis the peak response of acebutolol obtained from the
Standard solution:not more than 0.5%of any individual impurity is found.The sum of all individual impurities found in
Test 1and
Test 2is not more than 1.0%.