磷钼杂多酸示波极谱法测定痕量半胱氨酸

Linear Scan Polarography Determination Of Trace Amount Of Cysteine With Phosphorus molybdenum Heteropoly Acid

本文研究了半胱氨酸在室温下与磷钼杂多酸的反应,产物在P^H=9.8的氨一氯化铵缓冲溶液中有一灵敏的导数阳极吸附波可用于半胱氨酸的定量测定。半胱氨酸浓度在1×10~8mol/L～5×10^(-5)mol/L与导数波高有线性关系,检测限为5×10^(-9)mol/L。对混合样品中半胱氨酸的测定,回收率在94.5％～99.3％之间变化,相对标准偏差分别为0.4％和0.3％

A new method for linear scan Polarography determination of trace cysteine has been described. The method is based on the reaction of phosphorus- molybdenum heteropoly acid with cysteine . Optimum experi' mental conditions have been established. The determination range of 1 ×10-3 - 5×10-5mol/L and the determination limit of 5×10-9mol/L are given. The recovery is 94.5-99.3% and the coefficient of variation is 0.4% and 0.3%. when this method is used for determination of cysteine in mixed samples.