A metal-catalyst free, flexible and free-standing chitosan/vacuum-stripped graphene/polypyrrole three dimensional electrode interface for high performance dopamine sensing

Abstract

A three dimensional chitosan/vacuum-stripped graphene/polypyrrole interface with a hierarchical porous structure was fabricated as a free-standing and flexible electrochemical sensing electrode for dopamine detection, which exhibits unprecedented good selectivity, high sensitivity (632.1 μA mM⁻¹ cm⁻²), wide linear response range (0.1–200 μM), low detection limit (19.4 nM, S/N = 3) and good sensing performance in human serum samples, outperforming the previously reported 2D and 3D graphene and/or the PPy modified electrode, and exhibiting comparable performance with the Au modified electrode.