Synthesis of nitrogen-doped graphene nanosheets decorated with gold nanoparticles as an improved sensor for electrochemical determination of chloramphenicol

•Nitrogen doped graphene decorated with gold nanoparticles were synthesized.•Au nanoparticles improved the surface area and electron transfer properties of N-G.•Au/N-G composite markedly enhanced the voltammetric response of chloramphenicol.•CAP in real sample was successfully determined on Au/N-G modified electrode.

Nitrogen-doped graphene nanosheets decorated with gold nanoparticles (Au/N-G) were synthesized by the reduction of HAuCl4 on the surface of N-G using ethylene glycol as the reducing agent. The surface characterization with various techniques such as scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy showed that many gold nanoparticles were effectively loaded on the surface of N-G via the proposed synthesis process. The impedance analysis indicated that Au/N-G was an excellent electrode material possessing outstanding electrochemical features for electron transfer. Using Au/N-G modified electrode, the electrochemical response of chloramphenicol (CAP) was significantly increased due to the synergetic effect of two nanomaterials. Thus, a high-performance electrochemical sensor for CAP based on Au/N-G was developed.