▎ 摘　　要

We report a facile, rapid, phase-transfer-assisted process to prepare Ag nanoparticles (AgNP) loaded graphene oxide (GO) nanocomposite, by using cysteine as a highly-effective phase transfer agent for AgNP movement from organic phase to water and subsequently as a covalent linkage for immobilizing AgNP on GO. The obtainedc-Ag/GO nanocomposite possesses high nanoparticle loading efficiency, small particle size and monodispersity, strong binding force and good water dispersibility, which endow it with great potential in a variety of bio-applications. To illustrate potentail application,c-Ag/GO and its derivativesc-Ag/rGO were used for antibiosis and biosensing, respectively. Thec-Ag/GO composite demonstrates high antibacterial activity againstE. coliwith a minimal bactericidal concentration of 10 mu g ml(-1). The biosensor based onc-Ag/rGO exhibits rapid and sensitive response for uric acid detection with a detection limit of 0.025 mu M, a sensitivity of 5.76 mu A mM(-1)and a wide linear range of 0.025 similar to 2250 mu M. The comparative analysis with relevant nanocomposites also reveals the precedence ofc-Ag/GO in these applications, thus highlighting the advantages of the developed preparation method forc-Ag/GO.