meso-四(4-甲基-3-磺酸苯基)卟啉的合成及其光度法测定痕量锌、铜的研究  

Sythesis of Meso-Tetra(4-Methyl-3-Sulfophenyl) Porphine and Study on the Spectrophometric Determination of Trace Zinc and Copper

作　　者：陈秀华[1] 王莉红[1] 陈章弟 梅盛华 

机构地区：[1]杭州大学化学系

出　　处：《杭州大学学报（自然科学版）》1992年第4期420-425,共6页Journal of Hangzhou University Natural Science Edition

摘　　要：本文合成了水溶性meso-四(4-甲基-3-磺酸苯基)卟啉试剂[简称T(4-MP)PS_4]以光度法研究了该试剂在水溶液中的酸碱平衡和不同酸度下的存在形式,测得其pK_(a1)、pK_(a2)分别为4.80、6.10,并以光度法研究了同一样品中分别测定痕量锌、铜的方法和条件.实验表明,在pH4.10时,该试剂与锌、铜可以同时显色,显色后加入一定量HCl,能使锌配合物分解,而铜配合物不分解,从而消除了锌对铜测定的干扰;当锌含量大大超过铜含量时,铜对锌的测定不干扰.本文探讨了同一试剂分别测定同一实物中锌、铜含量的方法.方法灵敏度高.锌、铜配合物的摩尔吸光系数分别为3.10×10~5、2.10×10~5L·mo1^(-1)·cm^(-1)。本方法用于食品中痕量锌、铜的测定,所得的结果令人满意.Sythesis of meso-tetra (4-methyl-3-sulfophenyl) porphine [T(4-MP)PS4] and its acid-base equilibrium in aqueous solution have been studided. The ionization constants of T(4-MP)PS4 were determined with spectrophotometric method, the pKa1, pKa2 are 4.80, 6.10, respectively. The methods for the spectrophotometric determination of trace zinc and copper have been established. The experiments showed that the reagent can react simaltaneous with zinc and copper at pH4.1, then addition of dilute hydrochloric acid into the complexs, the zinc, complex can be decomposed and copper complex can not. Tolerance limits of the reagent, the Zn(Ⅱ) complex and the Cu(Ⅱ) complex lies at 437.6 nm, 422.8 nm and 437.1 nm respectively at pH4.1. The apparent molar absorptivities of the Zn(Ⅱ) complex and the Cu(Ⅱ) complex are 3.1×105, 2.1×105, respectively, Beer's law is obeyed for Zn(Ⅱ) of 0-3.0μg/25ml and for Cu(Ⅱ) of 0-6.0μg/25ml. The method can be successfully applied to the direct determination of trace zinc and copper in food.

关 键 词：T(4-MP)PS 锌 铜 分光光度法 

分 类 号：O657.3[理学—分析化学]