亚微米铂粒子修饰电极液相色谱电化学检测巯基化合物的研究  

Submicrometer-size Pt particles modified electrode for thiols in HPLC

作　　者：李金花[1] 徐海红[1] 曹旭妮[1] 金利通[1] 

机构地区：[1]华东师范大学化学系,上海200062

出　　处：《化学传感器》2003年第3期14-22,共9页Chemical Sensors

基　　金：国家自然科学基金(No.20175006);上海纳米科学技术项目(No.0114 nm 072)的资助项目

摘　　要：该文研究了亚微米铂粒子修饰电极的制备方法。并将该修饰电极与高效液相色谱脉冲安培检测法(HPIC-PAD)联用,分别检测了半胱氨酸(L-Cys)、谷胱甘肽(GSH)和青霉胺(PEN)三种巯基化合物。结果表明该修饰电极对这三种巯基化合物有良好的催化氧化作用;由于PAD的周期性的阳极高电位和阴极低电位能很好地清洗和再活化电极表面,应用PAD方法能有效提高巯基化合物的电流响应。此外,结果还表明,L-Cys、GSH和PEN的电流响应与其浓度呈现良好的线性关系,其检出限分别为1.1×10^(-7)mol/L、1.8×10^(-7)mol/L和3.8×10^(-7)mol/L(S/N=3)。与微渗析技术联用,该方法成功地用于大鼠脑中L-Cys和GSH的测定。这为电分析化学在临床医学、生理学等生命科学中的应用提供了新的手段。A new chemically modified electrode (CME) based on the immobilization of submi-crometer - size Pt particles is fabricated. It is found that the CME exhibits efficiently electro-catalytic oxidation for L - cysteine (L-Cys), glutathione (GSH) and penicillamine (PEN) with relatively high sensitivity. Coupled with HPLC, the CME is utilized for pulsed amperometric detection of these thiols. The results indicate that utilization of pulsed amperometric detection can effectively improve the responses of these thiols because of alternated anodic and cathodic polarizations to clean and reactivate the CME surface. It shows that the peak currents of L - Cys, GSH and PEN are linear to their concentrations with the calculated detection limit of 1. 1 × 10 -7, 1. 8× 10 -1 and 3. 8 × 10 -7 mol/L, respectively. The method has been successfully applied to assess the contents of L - Cys and GSH in rat striatal microdialysates.

关 键 词：亚微米铂粒子 修饰电极 液相色谱 电化学检测 巯基化合物 半胱氨酸 谷胱甘肽 青霉胺 

分 类 号：O657.7[理学—分析化学]