A highly flexible and selective dopamine sensor based on Pt-Au nanoparticle-modified laser-induced graphene

A highly flexible and selective electrochemical sensor based on a Pt–Au nanoparticles (Pt-AuNPs) modified laser-induced graphene (LIG)/Polydimethylsiloxane (PDMS) electrode is presented for the detection of dopamine (DA). The Pt-AuNPs exhibited high electrocatalytic activity in response to the oxidation of DA, and the peak current of DA detected by the Pt-AuNPs/LIG/PDMS electrode linearly increased with DA concentration. The fabricated sensor also exhibited an excellent sensitivity of approximately 865.80 μA/mM cm−2 and a detection limit of 75 nM in a neutral solution. In addition, it showed high selectivity for interfering compounds such as uric acid (UA) and ascorbic acid (AA). Clearly defined current peaks, with a separation of approximately 0.11 V, were observed for DA and UA. Finally, DA was successfully detected in human urine.