利用Origin软件确定西索米星的离解常数

The determination of polybasic ionization constants of sisomicin with origin software

采用电位滴定法测定西索米星的离解常数;用Origin 软件对西索米星的电位滴定数据进行处理,并用Origin 软件拟合了在不同pH 值条件下西索米星各价态离子的分布曲线,此法快速简便,无需编程。报道了西索米星的五级离解常数为pK_(b1)=5.008,pK_(b2)=5.397,pK_(b3)=5.916,pK_(b4)=6.488,pK_(b5)=7.057,为西索米星的分离提取提供了重要的依据。

Sisomicin was assayed by potentiometric titration method,which was quite sensitive and accurate.The potentiometric titrationdata were dealt with to get the stepwise ionization constants of Sisomicin by subsection-linearity regress and simultaneous equations withOrigin software.The distribution of different charged-ion of Sisomicin in different pH conditions was simulated also with Origin software,which was speed and convenient and needless programing.The five stepwise ionization constants of Sisomicin(pK_(b1)=5.008,pK_(b2)=5.397,pK(b3)=5.916,pK_(b4)=6.488,pK_(b5)=7.057)were reported,which applied to the purification of Sisomicin.