离子色谱安培法测定尿液中的胱氨酸

建立离子色谱安培法检测尿液中胱氨酸的分析方法。将尿液稀释处理后,过OnGuardⅡRP前处理柱,去除尿液中的有机物,选用低容量阳离子交换柱IonPac CS17进行分离,以甲烷磺酸梯度淋洗,柱后用300 mmol/L NaOH溶液衍生,离子色谱脉冲安培法检测,外标法定量。胱氨酸的质量浓度在0.1~5.0 mg/L范围内与其色谱峰面积呈良好的线性,线性相关系数r^2=0.999 9,检出限为0.05 mg/L。测定结果的相对标准偏差为0.71%(n=6),样品加标回收率为94%~108%。该方法具有操作简单,专属性强,灵敏度高等优点,可用于临床快速检测尿液中的胱氨酸。

Determination of Cystine in Urine by Ion Chromatography with Pulsed Amperometric Detection

The method for the determination of cystine in urine was developed by ion chromatography with pulsed amperometric detection. The urine sample was diluted,then the organic matter in the urine was removed by a OnGuardⅡ RP pretreatment column,and the filter liquor was separated by using low capacity of cation exchange column IonPac CS17 with methane sulfonic acid as gradient elution,and derived by 300 mmol/L NaOH solution,the content of cystine in urine was determined with ion chromatography pulse ampere method and external standard method. The mass concentration of cystine in urine had good linear relationship with the chromatography peak area in the range of 0.1-5.0 mg/L with the correlation coefficients(r2) of 0.9999. The detection limit of the method was 0.05 mg/L. The relative standard deviation of determination results was 0.71％(n=6). The recovery of sample was 94％-108％. The method is suitable for the determination of cystine in urine with a simple operation,high specificity and sensitivity.