▎ 摘　　要

A simple, facile, eco-friendly and rapid synthesis of gold nanoparticles (GNPs) derived from B. javanica Blume leaves extract (BJBLE) was successfully developed. The GNPs were formed within 40 sec and it was confirmed by UV-visible spectroscopy. The BJBLE acts as a (strong) reducing and (as well as) stabilizing agent. The Chemical constituents of BJBLE were studied by GC-MS. The prepared GNPs are spherical in shape and the particles size around 25 nm, which was confirmed by HR-TEM. The formation of GNPs and interaction between the plant extract was characterized by XRD and FTIR. One step preparation of graphene oxide encapsulated GNPs (GO/GNPs) was confirmed by SEM and EDX spectrum. The electrochemical activities of the GO/GNPs modified electrode were characterized by CVs and DPV. The electrochemical results demonstrate notable electrocatalytic activity of the GO/GNPs modified glassy carbon electrode (GCE) towards dopamine detection. The GO/GNPs modified GCE displayed a wide linear range with a low detection limit of 0.03 11M and good selectivity towards dopamine even in the presence of biologically co-interfering substances. The above results suggested that the GO/GNPs modified GCE is very promising and active electrode material for the detection of dopamine for pharmaceutical and clinical applications.