掺杂修饰碳糊电极对蔬菜中镉的电化学快速检测  

Rapid Electrochemical Determination of Cd in Vegetables Using Doping ModifiedCarbon Paste Electrode

作　　者：罗惠莉[1,2] 张舸帆 黄一璐 龙雯琪 周颖 Luo Huili;Zhang Gefan;Huang Yilu;Long Wenqi;Zhou Ying(College of Environment and Ecology,Hunan Agricultural University,Changsha 410128;State Environmental Protection Key Laboratory of Monitoring for Heavy Metal Pollutants,Changsha 410019;Hunan National Standard Testing Technology Company,Changsha 410005)

机构地区：[1]湖南农业大学环境与生态学院,长沙410128 [2]国家环境保护重金属污染监测重点实验室,长沙410019 [3]湖南国标检测科技有限公司,长沙410005

出　　处：《中国食品学报》2023年第9期368-375,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家环境保护重金属污染监测重点实验室开放基金项目(SKLMHM202112);第二次全国污染源普查专项项目(CLPSP18GZ02ZC95)。

摘　　要：目的:本研究旨在建立一种适用于高含水蔬菜中Cd快速检测的电化学分析方法。方法:通过调整纳米氧化铝/氧化铋的掺加比进行碳糊电极的修饰优化;通过分析各基质对检测的影响,确定基质稀释比和检测条件;基于基质中主要金属元素的含量,分析了主要干扰离子的影响。结果:氧化铝/氧化铋掺杂比为20%,采用此掺杂修饰碳糊电极(DMCPE),以方波阳极溶出伏安法(SWASV)检测Cd的线性范围为0.2~70μg/L,线性方程为:Ip=0.1774C+0.3646,相关系数r=0.9983。3种基质:黄瓜、西红柿、小白菜稀释比分别为30,60和100时,对Cd检测添加回收率为87.45%~101.14%。基质对Cd检测的影响为小白菜>西红柿>黄瓜。蔬菜中高含量的Zn2+、Mg2+对Cd的电化学检测有干扰,其中Zn2+干扰最大。SWASV法对Cd检测值可达到ICP/MS检测的87.25%~108.25%。结论:蔬菜样品经过匀浆-HNO3稀释-超声提取的前处理后,采用本研究建立的DMCPE-SWASV法可以准确快速测定其中的Cd。本研究结果为开发低成本、稳定且易操作的农产品重金属快速检测技术提供参考。Objective:Aim of this study was to establish an electrochemical method for rapid detection of Cd in high water vegetables.Methods:The modification of carbon paste electrode was optimized by adjusting the doping ratio of nano-alumina/bismuth oxide.After analyzing the influence of each substrate on the detection,the dilution ratio of the substrates and the detection conditions were determined.Based on the content of main metal elements in the matrix,the influence of major interfering ions was analyzed.Result:The doping ratio of alumina/bismuth oxide was 20%.Linear range of Cd detection was 0.2-70μg/L by using this doped modified carbon paste electrode(DMCPE)through square wave anodic stripping voltammetry(SWASV),and the linear equation was as follows:Ip=0.1774C+0.3646 with correlation coefficient r=0.9983.The recoveries were 87.45%-101.14%in the detection of Cd when the dilution ratios of cucumber,tomato and cabbage were 30,60 and 100,respectively.The influence of matrix on Cd detection was as follows:cabbage>tomato>cucumber.High content of Zn2+and Mg2+in vegetables interfered with the electrochemical detection of Cd,among which,Zn2+interfered the most.The test value by SWASV method reached 87.25%-108.25%of ICP/MS detection.Conclusion:After homogenation-HNO3 dilution-ultrasonic extraction,Cd in vegetable samples can be determined accurately and quickly by this DMCPE-SWASV method.The results of this study provided a reference for development of low-cost,stable and easy-to-operate rapid detection technology for heavy metals in agricultural products.

关 键 词：蔬菜 镉 电化学 快速检测 

分 类 号：O657.1[理学—分析化学] TS255.7[理学—化学]