An Electrochemical Sensor Based on Platinum Nanoparticles and Mesoporous Carbon Composites for Selective Analysis of Dopamine

摘要

An electrochemical sensor was developed by in-situ electrodeposition of platinum nanoparticles (Pt NPs)on the surface of mesoporous carbon (MC). Due to the synergistic effect of Nafion film, Pt NPs, andMC, the as-prepared sensor (Nafion/Pt/MC/GCE) exhibited excellent electrocatalytic activity towardsthe oxidation of dopamine (DA). Moreover, the oxidation potential of DA on the sensor was perfectlydistinguished (no overlape) from those of uric acid (UA) and ascorbic acid (AA) on the sensor. Thedifferences in oxidation peak potential for UA?DA and DA?AA were 123 and 204 mV, respectively,which are sufficently large for the selective determination of DA. Electrocatalysis of DA on the sensorwas investigated by different pulse voltammetry (DPV) and chronoamperometry, revealing excellentcatalytic activity. The catalytic current obtained from the amperometric response was linearly dependenton DA concentration in the range of 0.1 to 193 μM (R 0.994). The sensitivity of DA detection wascalculated to be 12.23 μA mM–1, and the limit of detection (LOD) was calculated to be 0.034 μM.Therefore, due to its advantages of high stability, good reproducibility and selectivity, and attractivesensing ability, this sensor shows promise as a new strategy for the detection of DA in biological samples.