Electrodeposition one-step preparation of silver nanoparticles/carbon dots/reduced graphene oxide ternary dendritic nanocomposites for sensitive detection of doxorubicin

摘要

In this article, ternary nanocomposites consisting of silver nanoparticles (AgNPs), carbon dots (CDs) and reduced graphene oxide (rGO) were newly synthesized via a one-step electrodeposition method. Upon cyclic voltammetry (CV) scanning, ternary nanocomposites with dendritic structure were facilely generated and electrodeposited on glass carbon electrode (GCE), without involving toxic solvents and reducing agents. The nanocomposites were characterized by means of scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) techniques. Characterization results revealed that the nanocomposites showed dendritic structures and dispersible narrow-sized nanoparticles were deposited on the matrix of rGO, mainly attributed to the use of Ag(NH_3)_2OH instead of Ag(NO_3)_2 as the precursor. The nanocomposites deposited on GCE had superior electrocatalytic activities for doxorubicin (DOX) reduction. The electrocatalytic activities were strongly affected by Ag(NH_3)_2OH concentration. The best electrocatalytic activities could be obtained when the volume ratio of CDs-GO (3:1, v/v) to Ag(NH_3)_2OH was fixed to 1:1. The peak current intensities of AgNPs-CDs-rGO/GCE sensing system linearly increased upon the increase of coexisting DOX concentration in the range from 1.0 × 10~(-8) to 2.5 × 10~(-6) M (R~2 = 0.9956), together with a limit of detection as low as 2 nM.