胶体金快速定量法测定粮食中镉的方法鉴定

Identification of Cadmium in Grain Measured by Rapid Quantitative Method of Colloidal Gold Technique

为满足粮食收购现场对镉快速定量测定的需求,对基于酶受体竞争反应的胶体金快速定量法测定粮食中镉的检出限、定量限、准确性、重复性、稳定性、台间差和检测时长等参数进行了测试。结果表明该方法的检出限为17.23μg/kg,定量限为48.84μg/kg,均满足国家标准对粮食中镉的检测要求;与石墨炉原子吸收光谱法(国标方法)测定结果相比无显著性差异;单个样品从称量到读取数据35 min内即可完成;重复性、稳定性的标准差和极差以及台间差t检验值均符合LS/T 6402-2017《粮油检验设备和方法标准适用性验证及结果评价一般原则》的规定。

In order to meet the demand of rapid quantitative detection of cadmium in grain purchase site,the parameters such as the limit of detection,limit of quantitation,accuracy,repeatability,stability and inter-instrument agreement,detection duration of cadmium in grain,measured by rapid quantitative method of colloidal gold technique based on competitive reaction of enzyme receptors,were tested. The results showed that the limit of detection of the method was 17.23 μg/kg,and the limit of quantitation was 48.84 μg/kg,which both met the Chinese national standard for the detection of cadmium in grain. There was no significant difference compared with the results measured by graphite furnace atomic absorption spectrometry. For a single sample,it can be completed within 35 minutes from weighing to reading the data. The repeatability,standard deviation and range of stability,and Inter-instrument agreement t-test values are in accordance with the regulations of LS/T 6402-2017 "Inspection of Grain and Oil-The General Principle of Standard Adaptability Verification and Evaluation Results for Equipments and Testing Methods".