双波长共振瑞利散射法测定饮料中的苋菜红  

Determination of Amaranth in Drinks by the Dual-Wavelength Overlapping Resonance Rayleigh Scattering(DWO-RRS)Method

作　　者：薛家兴[1] 李春燕[1] 许倩影[2] 刘绍璞[1] 胡小莉[1] 

机构地区：[1]发光与实时分析教育部重点实验室/西南大学化学化工学院,重庆400715 [2]重庆材料研究院,重庆400707

出　　处：《西南大学学报（自然科学版）》2014年第5期100-104,共5页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金(20875078);重庆市科委重点实验室专项经费资助

摘　　要：在pH=2.8~3.4的Britton-Robinson（BR）缓冲溶液中,乙基紫（EV）与苋菜红（AT）形成3∶1的离子缔合物,导致双波长共振瑞利散射（DWO-RRS）显著增强,并产生新的RRS光谱.在最大RRS峰334nm和374nm处,散射增强程度（ΔI）与AT的质量浓度在0.1~6.0μg/mL范围内成良好的线性关系,检出限为12.9ng/mL（RRS,334nm）、12.4ng/mL（RRS,374nm）、6.3ng/mL（DWO-RRS,334nm＋374nm）.据此建立了灵敏度高、选择性好、快速准确测定AT的光散射新方法,适用于饮料中AT含量的测定.研究了RRS光谱特征和适宜的反应条件,并对EV与AT的结合模式进行了讨论.In pH 2.8~3.4Britton-Robinson（BR）buffer medium,ethyl violet（EV）and amaranth（AT） formed a 3∶1ion-association complex,which led to a great enhancement of dual-wavelength overlapping resonance Rayleigh scattering（DWO-RRS）and the occurrence of new RRS spectra.At the maximum scattering peaks（334nm and 374nm）,DWO-RRS enhancement（ΔI）and AT concentration showed a good linear relationship in the range of 0.1-6.0μg/mL,and the detection limits were 12.9ng/mL（RRS,334 nm）,12.4ng/mL（RRS,374nm）and 6.3ng/mL（DWO-RRS,334nm＋374nm）.Based on the above results,a highly sensitive,well selective,rapid and accurate new molecular spectrum method was proposed for AT determination in drinks.The RRS spectral characteristics and appropriate reaction conditions were studied.The combination modes of EV with AT were discussed.

关 键 词：乙基紫 苋菜红 共振瑞利散射 饮料 

分 类 号：O657.3[理学—分析化学]