铜、碘掺杂碳点过氧化物模拟酶比色探针检测茶叶中痕量Pb(Ⅱ)  

A Colorimetric Probe for Determination of Trace Pb(Ⅱ)in Tea Based on Peroxidase-like Activity of Carbon Dots Co-doped with Copper and Iodine

作　　者：程春生[1] 杨德志 李宏 李秋兰 杨亚玲[2] CHENG Chunsheng;YANG Dezhi;LI Hong;LI Qiulan;YANG Yaling(Faculty of Food Science and Engineering,Kunming University of Science and Technology,Kunming 650500,China;Faculty of Life Science and Technology,Kunming University of Science and Technology,Kunming 650500,China;Institute of Agro-products Processing,Yunnan Academy of Agricultural Sciences,Kunming 650032,China)

机构地区：[1]昆明理工大学食品科学与工程学院,云南昆明650500 [2]昆明理工大学生命科学与技术学院,云南昆明650500 [3]云南省农业科学院农产品加工研究所,云南昆明650032

出　　处：《食品科学》2021年第24期323-328,共6页Food Science

基　　金：云南省科技人才和平台计划-技术创新人才培养对象项目(202005AD160015);云南省科技创新及成果转化专项-云南省农科院科技专项(202002AE320007-03)。

摘　　要：基于Pb(Ⅱ)对铜、碘掺杂碳点模拟酶的活性调节,建立简单、灵敏测定茶叶中Pb(Ⅱ)的比色探针新方法。铜、碘掺杂碳点的动力学分析结果表明:其模拟酶催化参数符合典型的米氏方程模型。Pb(Ⅱ)吸附于铜、碘掺杂碳点表面后,可促进底物3,3’,5,5’-四甲基联苯胺(3,3’,5,5’-tetramethylbenzidine,TMB)的氧化。Pb(Ⅱ)在0.27~27.02 mg/L范围内呈良好的线性关系。将该方法用于Pb(Ⅱ)含量的测定,其检出限可达到34.3μg/L,实际茶叶样品的加标回收率在92.41%~101.85%范围内,满足GB 5009.12—2017《食品中铅的测定》中的检测要求。该方法具有简便、稳定、特异性强等特点,其检出限也低于国家规定的食品中Pb(Ⅱ)含量限值。Based on the regulation of Pb(Ⅱ)on the enzyme-like activity of carbon dots co-doped with copper and iodine(Cu,I-CDs),a novel,simple and sensitive colorimetric probe was established for the determination of Pb(Ⅱ)in tea samples.The kinetic parameters of Cu,I-CD peroxidase-like activity were well fitted to the Michaelis-Menten equation.When it was adsorbed on the surface of Cu,I-CDs,Pb(Ⅱ)could promote the oxidation of the substrate 3,3’,5,5’-tetramethylbenzidine(TMB).The concentration of Pb(Ⅱ)in the range of 0.27–27.02 mg/L showed a good linear relationship with the formation of oxidized TMB(oxTMB).The detection limit of the developed method was 34.3μg/L,and the spiked recoveries for actual tea samples were in the range of 92.41%–101.85%.These figures of merit meet the requirements of the national standard GB 5009.12-2017.In conclusion,this method is simple,stable,and specific,and its detection limit is lower than the country’s limit for Pb(Ⅱ)content in foods.

关 键 词：铅 铜、碘掺杂碳点 过氧化物模拟酶 比色探针 茶叶 

分 类 号：O652.1[理学—分析化学]