吸附镍(Ⅱ)的甘氨酸共价修饰玻碳电极的制备及应用于葡萄糖的无酶催化氧化测定  

Preparation of Glycine Covalently Modified GCE adsorbed with Ni(Ⅱ) and Its Application to Determination of Glucose by Non-enzymatic Oxidation

作　　者：景振辉[1] 林祥钦[1] 

机构地区：[1]中国科学技术大学化学系,合肥230026

出　　处：《理化检验（化学分册）》2011年第5期501-504,507,共5页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：国家自然科学基金项目(No.20575062)

摘　　要：将玻碳电极（GCE）置于0.01 mol·L-1甘氨酸的[Bmin]PF6离子液体溶液中,于0~2.0 V电位间以50 mV·s-1扫描速率进行循环伏安扫描10圈,从而制成通过C-N共价键结合的甘氨酸修饰玻碳电极（Gly/GCE）。将此修饰电极置于0.1 mol·L-1氯化镍溶液中浸泡6 h,镍（Ⅱ）就吸附于甘氨酸修饰层上,制成了吸附着镍（Ⅱ）的Gly/GCE,记作Ni（Ⅱ）-Gly/GCE。此电极在0.1 mol·L-1氢氧化钠溶液中由于Ni2＋/Ni3＋电对的媒介作用对葡萄糖产生无酶催化氧化反应,导致在＋0.55 V（vs.SCE）处氧化峰电流明显增高,电流响应值与葡萄糖浓度在1×10-6~2×10-3mol·L-1范围内呈线性关系,其检出限（3S/N）为3×10-7mol·L-1。据此,提出了测定葡萄糖的计时电流法,并应用于血清样品中葡萄糖的测定,所得结果与用Dimension RXL-MAX自动化分析仪的测定结果相符。The pretreated GCE was placed in a solution of 0.01 mol·L-1 glycine in ionic liquid PF6,and scanned cyclic-voltammetrically at the rate of 50 mV·s-1,in the potential range of 0 to 2.0 V for 10 cycles to prepare the glycine modified GCE（Gly/GCE） through covalent bonding between C and N.The Gly/GCE was then soaked in 0.1 mol·L-1 NiCl2 solution for 6 h to adsorb Ni（Ⅱ） onto the surface of the Gly layer to give the modified electrode of Ni（Ⅱ）-Gly/GCE.In 0.1 mol·L-1 NaOH solution,non-enzymatic oxidation of glucose was observed at this modified electrode due to the mediatory action of the redox half-reaction of Ni2＋/Ni3＋,leading to significant increase of oxidation peak current at the potential of ＋0.55 V（vs.SCE）.Linear relationship between values of current response and concentration of glucose was obtained in the range of 1×10-6-2×10-3mol·L-1 with the detection limit（3S/N） of 3×10-7mol·L-1.Based on these facts,a chronoamperometric determination of glucose was proposed and applied to the analysis of blood serum samples,giving results in consistency with the results found by the Dimension RXL-MAX automatic biochemical analyzer.

关 键 词：甘氨酸修饰玻碳电极 镍(Ⅱ) 安培测定法 无酶催化氧化 葡萄糖 

分 类 号：O657.1[理学—分析化学]