甘氨酸的荷移分光光度法测定

Spectrophotometric Determination of Glycine Based on Charge-transfer Reaction

文章用分光光度法研究了甘氨酸与四氯苯醌 ( TCBQ)的荷移反应 ,确定在 p H=9.0的硼砂缓冲溶液中 ,于 5 0℃水浴中恒温 60 min,可获得 1∶ 1的络合物 ,其λmax=35 0 nm,表观摩尔吸光系数 ε=1 .98× 1 0 4 L· mo L- 1· cm- 1线性范围为 0～ 2 .7× 1 0 - 5mo L/L.应用拟定的方法测定了甘氨酸制剂的含量 ,结果与文献方法一致 ,回收率为 95 .0 %～ 1 0 4 .2 %相对标准偏差为 0 .79% .

A new spectrophotometric method for the determination of glycine has been developed. It is based on a charge transfer reaction with Tetrachlorobenzoquinone to form a stable complex in borax buffer solution. The optimum conditions for this reaction have been studied. The composition of the complex is found to be 1:1 by Job’s method, the apparent molar absorptivity is determined to be 1.98×104L·mol -1·cm -1 at 350nm. Beer’s law is obeyed in the range of 0-2.7×10-5 mol/L. The recovery is in the range of 95.0 %～104.2 %. The relative standard deviation is 0.79 %. The proposed method has been successfully applied to the determination of glycine reagent.