Pt nanoparticles/reduced graphene oxide nanosheets as a sensing platform: Application to determination of droxidopa in presence of phenobarbital

- An electrochemical sensor is prepared by synergic effect of graphene and Pt nanoparticles.
- The sensor exhibits an excellent electrocatalytic activity towards simultaneous determination of droxidopa and phenobarbital.
- The proposed sensor showed high sensitivity and sub-micro molar detection limits.
- High efficiency obtained for pharmaceutical and biological analysis.

A simple electrochemical sensor has been developed based on the reduced graphene oxide/Pt nanoparticles nanocomposite immobilized on modified glassy carbon electrode (nPt-GN/GCE). The modified electrode displayed excellent electrochemical catalytic activities toward droxidopa (DDP) and phenobarbital (PB). The analytical performance of prepared electrode for the simultaneous determination of DDP and PB was investigated by using cyclic voltammetry and differential pulse voltammetry (DPV). The nPt-GN based sensor could separate the oxidation peak potentials of DDP and PB about 230 mV by DPV method. The calculated detection limits, obtained by DPV, for DDP and PB were 3.1 × 10−8 M and 2.36 × 10−8 M, respectively. The fabricated sensor was successfully applied to the detection of DDP and PB in real samples. The experiments illustrate that nPt-GN nanocomposite is a worthy electrode material which offers a large surface-to-volume ratio and improves the selectivity and sensitivity.

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