3D-porous laser-scribed graphene decorated with overoxidized polypyrrole as an electrochemical sensing platform for dopamine

•The overoxidized polymeric film (PPyox) was successfully deposited onto 3D-porous LSGE surface.•The developed sensor offers high sensitivity to dopamine (DA) due to the excellent catalytic activity of graphene active sites exposed at the surface.•This sensing platform exhibits an excellent selectivity toward DA in an excess amount of ascorbic acid thanks to the cation perm-selectivity of PPyox.•The sensor showed a low LOD of 7 nM under accumulation at an open circuit system and was successfully applied in human serum samples.