对乙酰氨基酚在L-半胱氨酸修饰金电极上的不可逆双安培测定  

Determination of acetaminophen based on L-cysteine modified gold electrode coupling irreversible biamperometry

作　　者：李利军[1] 陈其锋[2] 喻来波[2] 程昊[1] 冯军[2] 钟招亨[2] 孔红星[1] 吴健玲[2] 

机构地区：[1]广西工学院生物与化学工程系,广西柳州545006 [2]广西大学化学与化学工程学院,广西南宁530004

出　　处：《化学研究与应用》2008年第1期22-25,共4页Chemical Research and Application

基　　金：国家自然科学基金资助项目(20665001);广西科学基金资助项目(0640029);广西研究生教育创新计划(2006105930502m33)资助项目

摘　　要：在裸金电极上制备了L-半胱氨酸自组装膜修饰电极(L-Cys/SAM-CME),研究了对乙酰氨基酚(AP)在L-Cys/SAM-CME上的电化学行为,结果发现该修饰电极对AP的氧化具有催化作用,与裸金电极相比,氧化峰电位降低了68mV,峰电流增大了1.2×10-5A。本文探讨自组装膜修饰技术用于构建不可逆双安培法的可行性,利用对AP在L-Cys/SAM-CME上的催化氧化和高锰酸钾在裸金电极上的还原构建双安培检测体系,建立了在外加电压为0V条件下流动注射双安培法直接测定对AP的方法。在0V外加电压下,0.05mol/L硫酸载液中,测得对AP的峰电流与其浓度在2.0×10-7mol/L^2.0×10-4mol/L范围内呈良好的线性关系(r=0.9986,n=13),检出限为9.4×10-8mol/L。连续测定1.00×10-4mol/L的AP溶液20次,电流值RSD为1.90%,进样频率为80样/h。L-cysteine self-assembled monolayers modified electrode （L-Cys/Au SAMs） has been prepared on bare gold wire. The electrochemical behaviors of acetaminophen at the modified electrode are studied. The results shows that the potential of oxidation peak of acetaminophen reduce about 68mV, and the peak current increase about 1.2 × 10^-5A. The proposed method is based on the electrochemical oxidation of acetaminophen at the L-cysteine gold modified electrode and the reduction of permanganate at the bare gold electrode to form an irreversible biamperometric detection system. Under the external potential difference （△E） of 0 V, in the 0.05mol/L sulfuric acid, acetaminophen can be determined over the range of 1.0 × 10^-7 mol/L-2.0 × 10^-4mol/L（r = 0. 9986, n = 13） with a sample measurement frequency of 80 samples/h. The detection limit is 9.4 × 10^-8mol/L and the RSD for 20 replicate determination of 1.00 × 10^-4mol/L acetaminophen is 1.90%. This proposed method has the advantage of wide linear range, high selectivity and sensitivity. The disposal method of the sample is simple, and it is suitable to online analysis.

关 键 词：L-半胱氨酸 不可逆双安培法 修饰电极 对乙酰氨基酚 

分 类 号：O657.15[理学—分析化学]