Gold nanoparticles decorated reduced graphene oxide for detecting the presence and cellular release of nitric oxide

In this work, we report the preparation of a nanocomposite consisting of gold nanoparticles (AuNPs) electrochemically deposited on electrochemically reduced graphene oxide (ERGO), and its use for sub-micromolar detection of nitric oxide (NO). ERGO network provides highly conductive pathways for electron conduction and a large surface area for catalyst support, while AuNPs act as efficient electrocatalysts toward the oxidation of NO. The synergistic integration of ERGO and AuNP realizes the electrochemical detection of NO with high sensitivity (5.38 μA/μM/cm2), low detection limit (133 nM with a S/N = ∼5.5), and a fast response time (3 s). Furthermore, we demonstrate the use of the AuNP-ERGO hybrid electrode to detect the dynamic release of NO from live human umbilical vein endothelial cells (HUVECs).