基于瑞利光散射技术检测肉食中残留氯唑西林

Detection of Cloxacillin Residues in Meat Based on Rayleigh Light Scattering Technique

建立了快速、准确测定肉食中残留氯唑西林的高灵敏瑞利散射(RLS)新方法,对反应的适宜条件、共存物质的影响及RLS的光谱特征进行了探讨。在碱性介质中,氯唑西林与结晶紫反应生成二元紫色离子缔合物,使RLS信号显著增强,在最大RLS峰384 nm波长处,氯唑西林在0.007~0.44 mg/L范围内的质量浓度与体系的RLS增强强度(ΔIRLS)呈线性关系,检出限为0.0068 mg/L,定量限为0.015 mg/kg。方法用于生鲜猪肉及牛肉中残留氯唑西林含量的测定,回收率为96.9%~102%,相对标准偏差(RSD,n=5)为2.0%~2.8%。

A new,rapid,accurate and highly sensitive Rayleigh scattering(RLS)method was established for the determination of cloxacillin residues in animal meat.The suitable conditions of the reaction,the effects of coexisting substances and the spectrum characteristics of RLS were discussed.In alkaline media,cloxacillin reacted with leucocrystal violet to form a binary purple ionic associates complex,which led to a distinctly enhanced of RLS signal.At the 384 nm wavelength of maximum RLS peak,the mass concentration of cloxacillin in the range of 0.007 to 0.44 mg/L was directly proportional to Rayleigh scattering enhancement strength(ΔIRLS)of system.The detection limit was 0.0068 mg/L and the limit of quantitation was 0.015 mg/kg.The method was applied to the determination of cloxacillin residues in fresh pork and beef with the recoveries and the relative standard deviations(RSD)(n=5)ranging from 96.9%to 102%and from 2.0%to 2.8%,respectively.