In situ polymerization of highly dispersed polypyrrole on reduced graphite oxide for dopamine detection

A composite consisting of reduced graphite oxide and highly dispersed polypyrrole nanospheres was synthesized by a straightforward technique, by in situ chemical oxidative polymerization. The novel polypyrrole nanospheres can prevent the aggregation of reduced graphite oxide sheets by electrostatic repulsive interaction, and enhance their electrochemical properties in the nano-molar measurement of dopamine in biological systems with a linear range of 1–8000nM and a detection limit as low as 0.3nM. ••A novel strategy to improve the sensitivity of RGO polymer composite sensors was proposed.•RGO-highly dispersed PPy (RGO-HDPPy) composite was facilely synthesized.•The decorative PPy nanospheres could prevent the aggregation of RGO sheets.•RGO-HDPPy sensor offered a nanomole level detection for DA in biological systems.