Ma Dong-Lan, Wang Yun, Ma Kuang-Biao, Wang Jin-Ye
College of Chemical and Environmental Science, Henan Normal University, Xinxiang 453007, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2009 Oct;29(10):2833-7.
The N-(m-methylphenyl)-N'-(sodium p-aminobenzenesulfonate)-thiourea (MMPT) was good reagent of water solubility. In the medium of an HAc-NaAc buffer solution and hexadecyltrimethylammonium bromide (CTMAB), MMPT can react with platinum (IV) and palladium (II) to form green and brown soluble complex. The maximum absorbance of the complex was at lambdaPt(max) = 754.4 nm and lambdaPD(max) = 304.6 nm. Beer's law was obeyed with the concentration in the range of 0-32.0 microg Pt(IV)/25 mL and 0-25.0 microg Pd(II)/25 mL for platinum (IV) and palladium(II) respectively. The correlated coefficient was r754.4 = 0.999 5 for platinum (IV); and r304.6 = 0.999 9 for palladium (II). Their molar absorption coefficients were epsilonPT(754.4 = 8.6 x 10(4) L x mol(-1) x cm(-1) and epsilonPd(304.6) = 7.4 x 10(4) L x mol(-1) x cm(-1) respectively. The contents of platinum (IV) and palladium (II) were converted by determination of the absorbency of mix solution of platinum (IV) and palladium (II) at 754.4 and 304.6 nm. Only Cu2+ and Co2+ interfered with the determination of palladium (II) among 50 coexistent ions, so the selectivity was good. It can be used for the determination of content of synthesis samples. The relative standard deviation (RSD) was less than 2.0%, and the recovery (%) was in the range of 96%-104%. The results are satisfactory. Because the reagent reacts with platinum (IV) and palladium (II) to form water soluble complex and does not require pre-separation for simultaneous determination of platinum (IV) and palladium (II), the method is easy to operate, rapid and environment-friendly.
N-(间甲苯基)-N'-(对氨基苯磺酸钠)-硫脲（MMPT）是一种水溶性良好的试剂。在HAc-NaAc缓冲溶液和十六烷基三甲基溴化铵（CTMAB）介质中，MMPT能与铂（IV）和钯（II）反应形成绿色和棕色的可溶性络合物。该络合物的最大吸收波长分别为λPt(max)=754.4nm和λPd(max)=304.6nm。铂（IV）和钯（II）的浓度分别在0 - 32.0μg Pt(IV)/25 mL和0 - 25.0μg Pd(II)/25 mL范围内遵守比尔定律。铂（IV）的相关系数为r754.4 = 0.9995；钯（II）的相关系数为r304.6 = 0.9999。它们的摩尔吸收系数分别为εPT(754.4)=8.6×10⁴L·mol⁻¹·cm⁻¹和εPd(304.6)=7.4×10⁴L·mol⁻¹·cm⁻¹。通过测定铂（IV）和钯（II）混合溶液在754.4nm和304.6nm处的吸光度来换算铂（IV）和钯（II）的含量。在50种共存离子中，只有Cu²⁺和Co²⁺干扰钯（II）的测定，因此选择性良好。可用于合成样品含量的测定。相对标准偏差（RSD）小于2.0%，回收率（%）在96% - 104%范围内。结果令人满意。由于该试剂与铂（IV）和钯（II）反应形成水溶性络合物，无需预先分离即可同时测定铂（IV）和钯（II），该方法操作简便、快速且环保。
