Electrochemically sensitive determination of dopamine and uric acid based on poly (beryllon II)/nanowires-LaPO4 modified carbon paste electrode

A sensitive and selective electrochemical sensor based on poly (beryllon II)/nanowires-LaPO4 composite film modified carbon paste electrodes (CPE) was successfully constructed and used to study the catalytic oxidation of dopamine (DA) and uric acid (UA). Scanning electron microscope (SEM) and electrochemical techniques were used to characterize the properties of the modified electrode. The sensor exhibits strong electrochemical catalytic activity toward the oxidation of DA and UA thanks to synergic effect of poly (beryllon II)/nanowires-LaPO4 in 0.1 M phosphate buffer solution (pH 7.0). By using of differential pulse voltammetry (DPV), linear calibration curves are obtained as 0.10-31.60 and 39.38-403.28 mu M for DA and 0.82-682.94 mu M for UA. The detection limits are 0.03 mu M and 0.23 mu M for DA and UA, respectively. Moreover, this electrochemical sensor was applied to the simultaneous detection of DA and UA with high sensitivity and selectivity. Furthermore, the modified electrode displayed high reproducibility and stability for these species determination. Thus, the proposed sensor could be advantageously employed for the determination of DA in real pharmaceutical formulations. (C) 2013 Elsevier B.V. All rights reserved.