A Porphyrin‐functionalized Graphene Oxide Nanocomposite for Simultaneous Detection of Dopamine and Uric Acid

Abstract Carbon nanomaterials combined with porphyrins having the similar electrocatalytic active center to heme protein are quite promising for high‐performance nonenzymatic electrochemical sensor. Herein, the catalytic tetra(4‐aminophenyl) porphyrin (TAPP) molecules are covalent immobilized on the conductive graphene oxide (GO) surface (TAPP@GO) by a simple one‐pot method. TAPP@GO as a novel electrochemical sensor successfully realized the sensitive detection of dopamine (DA) and uric acid (UA) in nM level with high stability and repeatability. The detection limit (LOD) for DA and UA is as low as 38 and 47 nM, and sensitivity up to 40.3 and 54.2 μA mM⁻¹ in a wide detection range from 0.1 to 350 μM, respectively. Impressively, both DA and UA in the coexistence system can be simultaneously determined with the LOD of 51 and 64 nM for DA and UA, which is further confirmed by accurate determination of both in urine samples. This work represents not only the first example of electrochemical sensor based on organic porphyrin molecules covalent linked on GO surface, but more importantly provides an effective method for developing high‐performance sensing materials.