摘要
用Nafion和碳纳米管联合修饰玻碳电极,探讨铅离子在修饰电极上的溶出伏安行为。建立了基于化学修饰电极检测大米中铅的溶出伏安电化学传感方法。实验结果表明,在pH值4.0、0.1mol/L醋酸-醋酸盐溶液的缓冲体系,富集电位-0.6V,富集时间180s,铅离子浓度在0.01～1mg/L范围内与溶出峰电流呈现良好的线性关系,检测限可达5μg/L,达到大米卫生标准。该方法操作简便,检测时间不超过5min,适合大批量大米样品检测,具有很好的准确性、灵敏度和稳定性。为进一步研究重金属现场快速检测奠定良好的实验基础。
A new method based on Nafion and multiwalled carbon nanotube（MWCNT） modified glass carbon electrode（GCE） has been established for rapid detection of lead in rice sample.The electrochemical behavior of lead on the modified GCE was investigated and the sensor signal was recorded using stripping voltammetry.The results showed that under the optimized conditions including 0.1 mol/L NaAc-HAc usded as surporting buffer（pH4.0）,-0.6 V of accumulating potential,180 s of accumulating time,an excellent linear sensor response of stripping peak current was displayed to the concentration of lead ion in the range from 0.01 mg/L to 1 mg/L with a detecting limit of 5 μg/L,showing favorable sensitivity to meet the National Standard for lead quantification in rice.In addition,this methods showed the advantages of short assay time（within five minutes）,good acuracy,satisfactory efficiency and stability for determination of lead in large amount of samples.Consequently,this technique provided primitive experimental model for fast detection of heavy metals on the sites.
出处
《食品科技》
CAS
北大核心
2011年第7期294-297,共4页
Food Science and Technology
关键词
NAFION
碳纳米管
铅
溶出伏安法
大米
Nafion
multiwalled carbon nanotube
lead
stripping voltammetry
rice
