Potentiometric Dopamine Sensor Based on Static and Dynamic Measurements

In this study, a sensor was proposed, which is modified with tungsten trioxide nanoparticles (WO
$_{\text{3}}$
NPs) on a cuprous oxide (Cu
$_{\text{2}}$
O) film for dopamine (DA) detection. We researched the performance of the sensor using electrochemical impedance spectroscopy (EIS) and voltage-time (
V
–
T
) measuring system. The results demonstrate that the sensor exhibits excellent selectivity toward DA, avoiding interference from ascorbic acid (AA) and uric acid (UA). In this study, measurement experiments were conducted using a microfluidic system to analyze the average sensitivity at low flow rates (1.5–7.5
$\mu $
L/min) and high flow rates (10–50
$\mu $
L/min). We achieved a high sensitivity of 42.61 mV/decade at a flow rate of 20
$\mu $
L/min. A significant improvement in sensing characteristics under dynamic measurements was observed compared to results obtained under static conditions.