曙红Y共振光散射法测定水中十六烷基三甲基溴化铵

摘要

Based upon the phenomenon that cetyltrimethylammonium bromide ( CTAB) can associate with eosin Y and displays vigorous enhancement effect on resonance light scattering ( RLS) intensity, a novel method for the determination of trace amount of CTAB in water was developed. Experimental results showed that in a sodium citrate - hydrochloric acid buffer solution with pH = 4. 96, and with Tween 80 as the stabilizer of eosin Y - CTAB system, addition of trace amount of CTAB resulted in enhancement of the RLS intensity of eosin Y at wavelength of 440 ~ 600 nm and the maximum scatter peak at 538 nm. The enhanced intensity of RLS is directly proportional to the mass concentration of CTAB in the range of 0 -40 mg · L-1 and the limit of detection is 0. 012 mg · L-1. The method has high sensitivity and fairly good selectivity.%利用共振光散射(RLS)技术,通过曙红Y与阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)缔合产生强烈共振光散射增强效应,建立了一种测定阳离子表面活性剂CTAB的方法.实验结果表明,在pH=4.96的柠檬酸钠-盐酸缓冲介质中,采用吐温80作为曙红Y -CTAB体系的稳定剂,痕量CTAB的加入导致曙红Y在440～ 600 nm波长内的共振光强度增加,最大RLS峰位于538 nm处,其强度与CTAB的质量浓度在0～40 mg·L-1内成正比,检出限为0.012 mg·L-1.方法具有较高的灵敏度和良好的选择性,可用于水样中CTAB的测定.