Determination of Related Substances in Enalapril Maleate Dispersible Tablets by HPLC / 中国药师

ABSTRACT

Objective:To establish an HPLC method for the determination of related substances in enalapril maleate dispersible tablets.Methods:AKromasil100-SC8(250mm×4.6mm,5μm)columnwasused. ThemobilephaseAwas0.01mol·L-1potassi-um dihydrogen phosphate (adjusting pH to 2. 2 with phosphoric acid) and mobile phase B was acetonitrile with gradient elution,and the flow rate was 1. 0 ml· min-1 . The detection wavelength was 215nm,the column temperature was 40℃,and the injection volume was 20 μl. Results:The linear range of enalaprilat,enalapril maleate and eanlapril diketopiperazine was 14.64-43.92 μg·ml-1(r =0. 999 8), 9. 29-27. 87 μg·ml-1(r=0. 999 1)and 10. 80-32. 40 μg·ml-1(r=0. 999 5), respectively. Enalaprilat was not detec-ted out and enalapril diketone was 0. 2% using the method described in Chinese pharmacopeia, and the content of enalaprilat was 0. 1% and that of enalapril diketone was 0. 2% using the gradient elution. The related substances and enalapril maleate could be sepa-rated well. Conclusion:The method is sensitive, accurate and highly specific in the quality evaluation and control.