对磺酸基苯亚甲基硫代若丹宁固相萃取光度法测定烟草添加剂中的汞

Study on Solid Phase Extraction and Spectrophotometric Determination of Mercury in Tobacco Additive with p-Sulfobenzylidene-thiorhodanine

合成了新试剂对磺酸基苯亚甲基硫代若丹宁(SBDTR),并用红外光谱、核磁共振氢谱和元素分析鉴定其结构。研究了SBDTR与汞的显色反应。在pH3.5的HAc NaAc缓冲介质中,吐温 80存在下,SBDTR与汞反应生成2∶1稳定络合物。该络合物可用WatersSep ParkC18固相萃取柱萃取,用乙醇洗脱后,在乙醇介质中用分光光度法测定,体系摩尔吸光系数为8.36×104L·mol-1·cm-1。汞含量在0～4μg/mL内符合比耳定律。本方法可用于烟草添加剂中汞含量的测定,结果满意。

A new chromogenic reagent, p-sulfobenzylidene-thiorhodanine (SBDTR) was synthesized, and its structure was verified by elemental analysis, IR, and^(1)H NMR. The color reaction of mercury with SBDTR was studied. In the presence of pH=3.5 HAc-NaAc buffer solution and Tween-80 medium, SBDTR reacted with mercury (Ⅱ) to form a stable 2∶1 complex. This complex was extracted by Waters Sep-Park C_(18) cartridge and the retained chelate was eluted by ethanol. The molar absorptivity was 8.36×10^(4) L·moL^(-1)·cm^(-1) at 555 nm. Beer's law was obeyed in range of 0～4 μg/mL. This method has been applied to the determination of mercury in tobacco additive with satisfactory results.