甲基紫共振光散射光谱法测定日落黄  

Determination of sunset yellow with methyl violet by resonance light scattering

作　　者：谢志海[1] 刘宇[1] 魏永锋[1] 蔡清[1] 王玲燕[1] 

机构地区：[1]西北大学,合成与天然功能分子化学教育部重点实验室,化学与材料科学学院,西安710069

出　　处：《分析试验室》2013年第3期103-105,共3页Chinese Journal of Analysis Laboratory

摘　　要：建立了甲基紫共振光散射光谱法测定饮料中日落黄的方法。在pH 3的B-R缓冲溶液中,日落黄与甲基紫之间相互作用形成离子缔合物,引起共振光散射强度的显著增加。共振光散射峰分别位于339 nm和650 nm处,在650 nm处,共振光散射强度与日落黄质量浓度在0.02～0.2 mg/L范围内呈现良好的线性关系(r2=0.9981)。考察了酸度、甲基紫用量、离子强度、温度等对体系光散射强度的影响,测定了缔合物的组成比。方法的检出限为7.5μg/L,相对标准偏差(RSD)为2.1%。方法用于饮料样品中日落黄的测定,结果与紫外分光光度法一致。A new method was developed for the determination of sunset yellow based on the resonance light scattering （RLS） technique. In the pH 3 B-R buffer solution, sunset yellow reacted with methyl violet （MV） to form an ion-association compound, which resulted in a significant enhancement of RLS intensity, and the RLS peaks located at 339 nm and 650 nm. The RLS intensity was proportional to the concentration of sunset yellow in the range of 0. 02 -0. 2 mg/L at 650 nm （r^2 = 0. 9981 ）. The influencing factors, such as solution pH, MV concentration, ion strength and temperature were investigated. The composition ratio of the ion-association compound was measured. The detection limit of the method was 7.5 μg/L, and the RSD was 2. 1%. This method was successfully applied to the determination of sunset yellow in soft drinks, and the results were in agreement with those by UV-Vis spectrophotometry.

关 键 词：共振光散射 日落黄 甲基紫 饮料 

分 类 号：O657.3[理学—分析化学]