A Sensitive Electrochemical Sensor Based on Au@Pd Hybrid Nanorods Supported on B-doped Graphene for Simultaneous Determination of Acetaminophen, Dopamine and Tyrosine

Abstract

In this report a fast and sensitive electrochemical sensor for simultaneous determination of DA, AC and Tyr was proposed based on the Au@Pd HNRs/BG hybrid nanocomposites. Firstly, the incorporation of B atom into graphene with porous framework was achieved by one-pot hydrothermal approach. Secondly, the Au@Pd hybrid nanorods (Au@Pd HNRs) were encapsulated in B-doped graphene (BG) to form Au@Pd HNRs/BG hybrid nanocatalysts. Interestingly, boron-doping effect introduce the highly dispersed COOH groups and abundant defect sites, which not only improve the interfacial properties of Au@Pd HNRs, resulting ultrathin BG effectively enwrapped most of individual Au@Pd HNRs with excellent dispersibility, but the -COOH units form hydrogen bonding with the phenolic hydroxyl groups of DA, AC and Tyr, which provide a large specific surface area to increase their loading amount and improve the excellent electro-catalytic effect the three analytes. Therefore, high enough anodic peaks potential separation of DA, AC and Tyr and increased peak currents at Au@Pd HNRs/BG/GCE was provided a simultaneous sensitively determination of them with extraordinary stability and cost effective analysis, the detection limits (S/N=3) for determination of DA, AC and Tyr were found to be 4.58, 6.35 and 3.71 μM, respectively. Finally, the as-fabricated sensor was satisfactorily used for the determination of DA, AC and Tyr in the urine sample with acceptable recovery range.