L-谷氨酸与维多利亚绿S作用机理及应用研究

用紫外-可见光度法、共振散射光谱法探讨了在弱酸性介质中,碱性染料维多利亚绿S与酸性氨基酸L-谷氨酸相互作用机理,认为L-谷氨酸分子通过盐键和氢键相互结合成含有亲水性基团的分子链,这条分子链可以将维多利亚绿S的疏水性基团包在里面,使其亲水性基团朝外,并通过盐键和氢键与维多利亚绿S作用形成大的聚合体,其聚合体体积远远大于染料自身聚集体的体积,使溶液颜色变深,分子光谱吸收值增加.并优化了反应体系酸度、反应物用量、反应时间、加试剂顺序等影响反应速度的因素,确定了最佳实验条件,建立了测定L-谷氨酸的方法.线性范围为10mg/L～100 mg/L,相关系数为0.9989.直接测定样品中谷氨酸获得满意结果.

Interaction between L-Glutamic Acid with Victoria Green S and Determination of L-Glutamic Acid

The interaction of L-Glutamic acid with Victoria Green S in pH 6.0 Britton-Robinson buffer solution has been investigated by UV/VIS spectrophotometry and resonance light scattering technique.It showed that L-Glutamic acids could link each other to form a long chain which contains many hydrophilic groups by salt linkages and hydrogen bonds in aqueous medium.Then the long chain surrounded the hydrophobic groups of Victoria Green S via hydrophobic interaction and reacted with Victoria Green S by salt linkages and hydrogen bonds in aqueous medium to form a macromolecular aggregation.The aggregation was much bigger than Victoria Green S itself.So the system's absorption and RLS increased and its colour became deeper.This interaction has been applied to the direct determination of L-Glutamic acid by spectrophotometry.The linear range for the determination of L-Glutamic acid is from 10mg/L to 100 mg/L with correlation coefficient of 0.9989 at 620 nm.The method has been used to the determination of L-Glutamic Acid in samples with satisfactory results.