高浓度抗坏血酸存在下氮掺杂石墨烯/壳聚糖修饰电极对尿酸的选择性测定  

Selective Determination of Uric Acid at Nitrogen-doped Graphene/Chitosan Composite Modified Electrode in the Presence of a Large Amount of Ascorbic Acid

作　　者：李宁波[1] 何凤云[1] 李丽[1] 胡耀娟[1] 白程超 段雨晴 

机构地区：[1]南京晓庄学院,环境科学学院,南京211171

出　　处：《分析化学》2015年第12期1859-1863,共5页Chinese Journal of Analytical Chemistry

基　　金：南京大学生命分析国家重点实验室开放研究基金(No.SKLACLS1308);江苏省大学生创新训练项目(No.201411460025Y);南京晓庄学院化学一级重点学科项目资助;supported by the National Natural Science Foundation of China(Nos.11254004;31460035)

摘　　要：采用一步水热合成法制备了氮掺杂石墨烯,采用滴涂法制备了氮掺杂石墨烯/壳聚糖修饰电极（N-GN-CS/GCE）,研究了在大量抗坏血酸存在下尿酸在此修饰电极上的伏安行为。结果表明,尿酸在此修饰电极上有一个明显的氧化峰,其峰电流约为裸电极的7倍;同时,氮掺杂石墨烯/壳聚糖复合修饰材料显著提高了尿酸对抗坏血酸的选择性,尿酸和抗坏血酸的峰电位差可达362 m V,可实现高浓度抗坏血酸存在下尿酸的选择性测定。优化了修饰材料的滴涂量、溶液pH值、扫描速度等实验参数,利用差分脉冲伏安法对尿酸进行测定,尿酸的脉冲峰电流与尿酸浓度分别在0.1~20μmol/L和20~400μmol/L浓度范围呈良好的线性关系,检出限为0.01μmol/L,相对标准偏差为3.3%（n=8）。将本方法用于实际尿样的测定,回收率为99.7%~103.4%。Nitrogen-doped graphene was synthesized by one-step hydrothermal method. A nitrogen-doped graphene-chitosan modified electrode（ N-GN-CS / GCE） was prepared and the electrochemical behavior of uric acid in the presence of a large amount of ascorbic acid was investigated at the modified electrode. The peak current of uric acid at the modified electrode was 7 times as that at unmodified electrode. The peak separation of uric acid and ascorbic acid was 362 m V and uric acid could be accurately determined in the presence of a large amount of ascorbic acid. Some experimental parameters such as dopping volume,p H and scan rate were optimized and a standard curve was also established using differential pulse voltammetry. The linear range between the peak current and the concentration of uric acid was 0. 1 ~ 20 μmol / L and 20- 400 μmol / L,and the detection limit was estimated to be 0. 01 μmol / L. The proposed method was applied to the analysis of uric acid in human urine sample with recoveries between 99. 7% and 103. 4%.

关 键 词：氮掺杂石墨烯 抗坏血酸 尿酸 

分 类 号：R446.12[医药卫生—诊断学] O657.1[医药卫生—临床医学]