Au nanoparticles decorated polypyrrole/reduced graphene oxide hybrid sheets for ultrasensitive dopamine detection

•A new strategy to improve the sensitivity of PPy/GS composite sensors is proposed.•Au@PPy/GS composite was facilely synthesized by the novel initiation of HAuCl4.•The prepared composite is dramatically obtained a crumpled and wrinkled surface.•The flower-like Au nanoparticles are decorated on the PPy/GS hybrid sheets.•Au@PPy/GS sensor offers an ultrasensitive detection for DA in biological systems. Au nanoparticles decorated polypyrrole/reduced graphene oxide hybrid sheets were facilely fabricated through a facile process. The prepared composite is dramatically obtained a crumpled and wrinkled surface, and uniform flower-like Au nanoparticles, which significantly improve the electrochemical properties in nano-molar level detection of dopamine. The novel sensor exhibits a remarkable sensitivity of 16.40μA/μM with a linear range of 0.1–5000nM and limit of detection as low as18.29pM.