聚L-精氨酸修饰柔性石墨烯平面电极对黄嘌呤的选择性检测  

A Flexible Electrochemical Sensor Based on L-Arginine Modified Chemical Vapor Deposition Graphene Platform Electrode for Selective Determination of Xanthine

作　　者：白志坤 张逸涛 李社红[1] 罗红霞[1] BAI Zhi-Kun;ZHANG Yi-Tao;LI She-Hong;LUO Hong-Xia(Department of Chemistry,Renmin University of China,Beijing 100872,China)

机构地区：[1]中国人民大学化学系,北京100872

出　　处：《分析化学》2020年第9期1149-1159,共11页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.21575160)资助。

摘　　要：在聚甲基丙烯酸甲酯(PMMA)的辅助下,将化学气相沉积(CVD)得到的石墨烯从铜基底转移到聚对苯二甲酸乙二醇酯(PET)基底上,制备了柔性石墨烯平面电极(GPE)。通过电化学沉积在GPE表面修饰L-精氨酸(L-Arg),得到聚L-Arg修饰的柔性石墨烯平面电极(P(L-Arg)/GPE)。用扫描电子显微镜(SEM)、能谱法(EDS)和拉曼光谱对此电极进行了表征。用循环伏安法(CV)和微分脉冲伏安法(DPV)研究了P(L-Arg)/GPE对黄嘌呤(XA)的电化学传感作用。在尿酸(UA)和次黄嘌呤(HX)存在下,P(L-Arg)/GPE传感器不仅实现了对XA的选择性测定,而且还成功实现了XA、UA和HX的同时测定,3个氧化峰的峰-峰电位差分别为420和384 mV。XA在0.5~8μmol/L和8~140μmol/L浓度范围内,响应电流与XA浓度分段呈良好的线性关系,检出限为0.08μmol/L(S/N=3)。此传感器具有稳定性好、重复性强、响应时间短、制作成本低、抗干扰能力强等优点,并成功应用于人血清中XA测定。A flexible graphene platform electrode(GPE)was prepared by transferring chemical vapor deposition graphene film from Cu foil to polyethylene terephthalate substrate with the help of polymethyl-methacrylate.L-Arginine(L-Arg)was electrodeposited on GPE to form poly(L-Arg)/GPE(P(L-Arg)/GPE)which was then characterized by scanning electron microscopy,energy dispersive spectroscopy and Raman spectroscopy.The electrocatalytic activity and enhanced conductivity of P(L-Arg)/GPE sensor was evaluated by determining xanthine(XA)in the presence of uric acid(UA)and hypoxanthine(HX)in phosphate buffer solution(PBS).The electrochemical behaviours of XA on P(L-Arg)/GPE were studied by cyclic voltammetry and differential pulse voltammetry in comparison with those on bare GPE.Further,the proposed sensor was used not only to achieve the selective determination of XA,but also to separate the voltammetric signals of UA-XA and XA-HX with potential differences of 420 and 384 mV,respectively.Under the optimized conditions,the proposed sensor displayed superb sensing property towards XA with a wide linear range from 0.5μmol/L to 140μmol/L,along with a detection limit of 0.08μmol/L(S/N=3).The P(L-Arg)/GPE was successfully applied to determine XA in human serum with good stability,reproducibility,high sensitivity,low cost as well as high resistance to interferences.

关 键 词：石墨烯平面电极 电化学传感 L-精氨酸 黄嘌呤 尿酸 次黄嘌呤 

分 类 号：O657.1[理学—分析化学] R446.1[理学—化学]