小麦籽粒中微量铅的快速测定技术

Technique for rapid determination of micro-plumbum in wheat grain

为建立一种快速测定粮食中微量铅的新方法,以南阳彩色小麦为材料,用微波压力消解技术快速处理样品,对测定条件进行优化,并与国家颁布标准方法(GB/T5009.12-2003)进行比较。结果表明:加标回收率为92.5%～96.8%,相对标准偏差RSD(Relative Standard Deviation)为0.67%～1.7%(n=11),铅的最低检出限为0.0099mg/L,测定的线性范围为0.850～206.0mg/L,相关系数为0.996,电极斜率为24.160。样品用该法与国标方法对照测定并进行显著性检验证明,该方法具有直观、快速、简便、灵敏、准确、适于现场进行测定的显著优点。

In order to establish .a rapid determination method of micro-plumbum in grain, Nanyang grey wheat, blue wheat, common violet wheat and violet hard-wheat were selected as materials, the materials were digested by microwave-assisted method under high pressure, and ions selective electrode with concentration direct reading was applied. The determination conditions were optimized. The veracity of rapid determination technique was compared with that of China standard（GB/T5009.12--2003）. The results showed that the recovery rate of standard addition was in the range of 92.5%--96.8%. The relative standard deviation was between 0.67% and 1.7%（n=11）. The lowest detection limit was 0.0099 mg/L.The linear range was 0.850--206.0 mg/L. The correlation coefficient was 0.996 and electrode slope was 24.160.This method is found to be direct-viewing, quick, simple, sensitive, accurate and the analytical results are satisfactory.