【摘要】 [目的]基于头孢氨苄降解产物中巯基(-SH)具有还原性,建立一种间接测定头孢氨苄的新方法。[方法]在0.1 mol/L Na OH存在下,一定量的头孢氨苄(CEX)于100℃水浴中进行降解30 min。其降解产物中的巯基在SCN-和KNO3存在下,将Cu(Ⅱ)还原成Cu(Ⅰ),所生成的Cu(Ⅰ)与SCN-反应生成白色乳状沉淀Cu SCN并能被浮至水相表面,水相中剩余Cu(Ⅱ)可与4-(2-吡啶偶氮)-间苯二酚(PAR)生成红色络合物(ε(510)=6.2×104L/(mol·cm)),根据吸光度测定剩余Cu(Ⅱ)的量间接计算头孢氨苄的含量。[结果]溶液中参加反应Cu(Ⅱ)的量C和头孢氨苄含量C0之间存在良好的线性关系:C=0.044 05+0.163 85 C0,线性范围为0.8～20μg/m L,相关系数R=0.999 3,检出限为0.4μg/m L。[结论]该方法用于测定头孢氨苄胶囊、空白血清头孢氨苄的含量,结果令人满意,可作为测定头孢氨苄新方法。更多还原

【Abstract】 [Objective]To obtain a new method to determine cefalexin by spectrophotometric, which is based on degrades and contains the base of-SH.[Methods]The degrades product of cefalexin can reduce Cu( Ⅱ) to Cu( Ⅰ) at p H 4. 0, and the resulting Cu( Ⅰ) reacts with SCN-to form obtain white milky precipitates,the absorbance of excess free copper is measured at the absorption maximum of 510 nm, and the amount of cefalexin can be indirectly calculated. [Results]Excess free copper and cefalexin has good linership which reacts in solution, linear over the range of 0.8 ～ 20 μg/m L, R = 0.999 3, detects of minimum is 0.4 μg/m L.[Conclusion]This method has been successfully applied to determine cefalexin in pharmaceutical and serum samples.更多还原