CTMAB增敏共振瑞利散射法测定食品中的铝

Determination of Aluminum in Food by Resonance Rayleigh Scattering Method with Cetyl Trimethyl Ammonium Bromide as the Sensitizer

在弱酸性Tris-盐酸缓冲介质中,溴化十六烷基三甲基铵（CTMAB）增敏氯酚红,并与Al（Ⅲ）结合生成三元络合物,使共振瑞利散射（RRS）显著增强并产生新的RRS光谱,最大共振散射峰位于337 nm,在一定条件下,共振瑞利散射增强程度（ΔIRRS）与Al（Ⅲ）的质量浓度成正比,线性范围在0.001 2-0.053 mg/L之间,方法具有很高的灵敏度,定量限为0.60 mg/kg。还研究了适宜的反应条件及影响因素,考察了共存物质的影响,表明方法具有良好的选择性。方法用于面制食品中Al的测定,结果满意。

In a weak acidic Tris-Hydrochloric acid buffer medium, cetyl trimethyl ammonium bromide （CTMAB） sensitization of chlorophenol red, and aluminum （III） could be bound with chlorophenol red-CTMAB to form a ternary complex, which led to a distinctly enhanced resonance Rayleigh scattering （RRS） and the appearance of a new RRS spectrum. The maximum resonance Rayleigh scattering peak was located at 337 nm for CTMAB and chlorophenol red and aluminum （III） system. Under certain conditions, the resonance Rayleigh scattering intensity （△IRRs） was directly proportional to the mass concentration of aluminum （III） in the range of 0.001 2 to 0.053 mg/L. The method exhibited high sensitivity, with the quantification limit being 0.60 mg/kg. At the same time, the optimal reaction conditions and the in fluencing factors were investigated, and the effects of coexisting substances were examined. Experiment showed that this method had a good selectivity. The method had been applied to the determination of aluminum in flour food with satisfactory results.