Sonochemical synthesis of ErVO4/MnWO4 heterostructures: Application as a novel nanostructured surface for electrochemical determination of tyrosine in biological samples

Present strategy introduces a novel method established for the synthesis of spherical shape ErVO4/MnWO4 heterostructures by a sonochemical method. This heterostructures with optima morphology can be synthesized by changing power and time ultrasound irradiation without any capping agent. BET analysis revealed that ErVO4/MnWO4 prepared in the presence of ultrasonic procedure has 75 times specific surface area as much as that of those was produced in the absence of ultrasonic rays. A variety of analyses (i.e., BET, XRD, TEM, EDS, FT-IR. and SEM) were applied for characterization of the ErVO4/MnWO4. Next, a selective and sensitive nanostructured sensor based on ErVO4/MnWO(4 )nanocomposite modified carbon paste electrode (ErVO4/MnWO4/CPE) was constructed for electrochemical detection of tyrosine (Tyr). The electrochemical characterizations were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Compared with the unmodified CPE, the oxidation peak current was significantly enhanced for Tyr. The impact of effective parameters on voltammetric response of Tyr was analyzed with design of experiments (DOE) and response surface methodology (RSM). Under the optimized conditions, the oxidation peak current of Tyr was linear over a range of 0.08-400.0 mu M with a detection limit of 7.7 nM. Finally, the usage of the proposed method was confirmed by the recovery tests of Tyr in biological samples. (C) 2019 Published by Elsevier Ltd.