Determination of Ionization Equilibrium Constant of Sildenafil by UV Spectrophotometry
- VernacularTitle:紫外分光光度法测定西地那非的电离平衡常数
- Author:
Xiangnan HU
;
Bo FAN
- Publication Type:Journal Article
- Keywords:
UV Spectrophometry;
Sildenafil;
Ionization equilibrium constant
- From:
China Pharmacy
1991;0(02):-
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To establish a method for determination of ionization equilibrium constant of sildenafil using ultraviolet spectrophotometry.METHODS:Methanol solutions of sildenafil with pH values of 2.26,8.56,9.31,9.83 and 12.38 were respectively scanned at the wavelength within the range of 200nm～400nm.The absorbability and pKa value of sildenafil were determined at the selected wavelength of 280,287,290,295 and 297nm respectively.RESULTS:The pKa value of sildenafil was 9.35?0.02.CONCLUSION:The present method is convenient and practicable.
