茚三酮比色法和旋光度法测定谷氨酸制备焦谷氨酸的转化率

摘要

研究了通过茚三酮比色法和旋光度法测定谷氨酸制备焦谷氨酸的转化率.通过紫外可见分光光度计在568nm,pH6.0状态下检测与茚三酮反应的谷氨酸和焦谷氨酸的含量.研究结果表明,谷氨酸具有较大的吸收峰,但焦谷氨酸吸光度为零.根据谷氨酸的标准曲线方程,可以计算其后反应溶液中的含量进而计算出转化率.基于谷氨酸和焦谷氨酸的旋光度—转化率工作曲线,可直接计算谷氨酸制备焦谷氨酸的转化率.结果表明,与高效液相色谱法相比,茚三酮比色法和旋光度法具有操作简单、快速、灵敏度高和成本低的优点.%Ninhydrin colorimetry and polarimetry were studied to determine the conversion of PCA prepared by glutamic acid.The content of Glu and PCA reacted with ninhydrin was detected by ultraviolet-visible spectrophotometer (UV/VIS) at 568nm,pH6.0.It was showed that Glu has a larger absorption peak,however the absorbance of PCA were zero.According to the standard curve equation of Glu,its content in the after-reacting solution can be calculated.Besides,the optimal rotation-conversion rate curves,by which the remaining Glu of the after-reacting can be calculated,were established on the basis of Glu and PCA optical rotation.The results indicated that compared with HPLC,ninhydrin colorimetry and polarimetry were simple,fast,highly sensitive and low-cost.