Template-based synthesis of uniform bimetallic nickel-tin oxide hollow nanospheres as a new sensing platform for detection of erythrosine in food products

In this work, for the first time, uniform nickel and tin bimetallic oxide was synthesized by calcining the carbon nanospheres (CNSs) templates. This novel synthesized bimetallic oxide was used to fabricate a modified carbon paste electrode (Ni-Sn-oxide NSs/CPE). This electrode was used as a high sensitive sensor for voltammetric determination of erythrosine (Er) in 0.1 mol L-1 phosphate buffer solution (PBS, pH 5.9). The synthesized bimetallic NSs were characterized by different techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and the X-ray diffraction (XRD). The hollow spherical nature of these Ni-Sn-oxide NSs was clearly revealed by the morphology studies. The dependence of oxidation peak current on pH of the solution, amount of modifier, scan rate, accumulation time and potential, interference effect and concentration of analyte were studied to optimize the experimental conditions. The experimental results suggested that the modified electrode have promoted electron transfer reaction for the oxidation of Er. The modified electrode exhibited effective surface area, more reactive sites and excellent electrocatalytic activity toward the oxidation of Er in two linear calibration ranges of 0.1-1 and 1-100 mu mol L-1 with detection limit of 2.1 nmol L-1. The novel proposed voltammetric method was successfully applied in the determination of Er in food products. The results indicated that the proposed method is sensitive, selective, fast and simple for determination of Er. (C) 2017 Elsevier B.V. All rights reserved.