树脂固相萃取在比色分析中的应用研究

Research on application of resin solid phase extraction in colorimetric analysis

针对可见光区蓝(磷钼蓝测硫体系)、黄(磺基水杨酸测铁体系)、红(a-萘胺测NO2-体系)3个典型波段,研究树脂固相萃取有色基团前后的吸光度变化,表明各波段固相比色分别较水相比色最大增长了53.67倍、20.04倍、10.50倍。实验确定了最佳树脂用量为3g,最佳萃取时间30min。模拟土壤、地质岩石及水质样品的复杂组合,表明树脂富集有色基团干扰不严重,方法可应用于各类样品中微量元素的比色分析。

Molybdenum blue measuring sulphur system, sulfosalicylic acid measuring iron system and α-naphthylamine colorimetric measuring nitrite ion system were studied in this paper. The absorbance after resin solid-phase extraction was compared with that before extraction, and the molar extinction coefficient, that is a multiple of the sensitivity, increased respectively 53.67, 20.04, and 10.50 times over the aqueous phase. The optimum amount of resin is 3 g, while the optimum extraction time is 30 min. The mixture system of water samples and soil samples or geological rock samples was simulated, which show that the interference of resin concentration was not great. This method can be applied to various types of colorimetric analysis of micro.