氧化石墨烯纳米带生物电化学传感器的研制及对氨基酸的检测

Preparation of bio-electrochemical sensor based on graphene oxide nanoribbon and its application in amino acid detection

目的 研制一种基于氧化石墨烯纳米带（Oxidized graphene nanobelts,GON）修饰的生物电化学传感器,用于L和D-氨基酸（AA）的快速检测。方法 采用2种石墨烯材料,氧化石墨烯纳米带（GON）和还原石墨烯纳米带（reduced graphene nanoribbons,GRN）,修饰于丝网印刷碳电极（CSPE）制备2种电极。利用D-AA和D-氨基酸氧化酶（DAAO）反应产生H_2O_2,然后以制备的电极通过差分脉冲伏安法（DPV）检测H_2O_2和L-AA电信号,并对电极和酶反应条件进行优化。选择具有电活性的酪氨酸（Tyr）为目标分析物,并对L-Tyr和D-Tyr进行定量分析,最后对其在尿样品中的Tyr含量进行检测。结果 在尿酸和其他电活性AA的存在下,该生物电化学传感器能够精确的检测出尿样中的L-Tyr和D-Tyr含量,其回收率分别为（95±5）%和（99±3）%。结论 该基于GON的电化学生物传感器可作为D-AA相关疾病的早期诊断工具,在临床早期诊断具有重要意义。

Objective To develop a bio-electrochemical based on oxidized graphene nanobelts （ GON） for rapid detection of L and D-amino acids （AA）.Methods Two kinds of electrodes were prepared using two types of graphene materials, graphene oxide nanoribbons and reduced graphene nanoribbons （GRN）, and modified with CSPE.H2O2, L-AA and electroactive molecular signals were detected by differential pulse voltammetry （DPV） using D-AA and D-amino acid oxidase （DAAO） reactions.In addition, two clinically relevant AA-tyrosine （Tyr） and methionine （Met）, which are electrically active, were examined and the L and D enantiomers were calibrated and quantified.Finally, the content in the urine samples were detected. Results The results of this study show that L-Tyr and D-Tyr in urine samples can be accurately detected in the presence of uric acid and other electroactive AA, and the recoveries are （95 ±5）% and （99 ±3）%, respectively.Conclusion The biosensor based on GON can be used as an early diagnostic tool for D-AA related diseases, which is of great significance in clinical early diagnosis.