毛细管电泳-电流突跃标记法测定磺胺甲噁唑磺胺嘧啶和甲氧苄啶的离解常数  

Determination of Dissociation Constant Values of Trimethoprim,Sulfadiazine and Sulfamethoxazole

作　　者：翟育忠[1] 李玉琴[2] 刘彩红[2] 郭丰广[2] 孝建华[3] 齐永秀[2] 

机构地区：[1]甘肃省疾病预防控制中心,兰州730000 [2]泰山医学院药学院,山东泰安271016 [3]泰山医学院附属医院,山东泰安271016

出　　处：《医药导报》2009年第4期420-423,共4页Herald of Medicine

基　　金：泰山医学院博士启动基金(基金编号:2006-742)

摘　　要：目的测定磺胺甲噁唑(SMZ)、磺胺嘧啶(SD)和甲氧苄啶(TMP)的离解常数(pKa)。方法毛细管电泳(CE)条件:未涂层的弹性石英毛细管柱(60.2cm×75μm,有效长度50cm),30mol.L-1磷酸盐缓冲液,恒电压,柱温25℃,检测波长214nm;阳极进样,阴极检测。电流突跃标记法测定中性标记物的电泳淌度。分别测定固定缓冲溶液的离子强度或不固定缓冲溶液的离子强度条件下三种化合物的有效淌度,并与pH值进行非线性拟合,测定其离解常数。结果SMZ、SD、TMP的离解常数固定离子强度时,分别为5.69,6.36和6.68;不固定离子强度时分别为5.71,6.35和6.60。结论该方法简便、快速、准确,可用于测定3种磺胺类药物的解离常数,且不受缓冲液离子强度的影响。Objective To develop a simultaneous determination of dissociation constant values （pKa） of sulfamethoxazole （SMZ）, sulfadiazine （SD） and trimethoprim （TMP）. Methods Capillary electrophoresis （CE） conditions： a fused -silica capillary column （60. 2 cm ×75 μm, effective length 50 cm） was used, the separation voltage was fixed, the cartridge temperature was 25 ℃, the UV detection wavelength was 214 nm, and sample was introduced from the anode with pressure injection. The mobility of neutral marker was determined with the current sudden change. The effective mobilities of the three compounds on pH were investigated, and their pKa values was determined by nonlinear simulation. Results When the ionic strength of running buffer was fixed, the pKa values of SMZ, SD and TMP were 5.69, 6.36 and 6.68, respectively ; on the contrary, the pKa values of SMZ, SD and TMP were 5.71 ,6.35 and 6.60, respectively. Conclusion The proposed method is simple, fast and accurate for determination the pKa values of suffonamides, and which isnt affected by the ionic strength of running buffer.

关 键 词：磺胺甲噁唑 磺胺嘧啶 甲氧苄啶 离解常数 毛细管电泳 电流突跃标记 

分 类 号：R978.2[医药卫生—药品] R969.1[医药卫生—药学]