New Bi2MoO6 nano-shapes toward ultrasensitive enzymeless glucose tracing: Synergetic effect of the Bi-Mo association

Abstract

In a novel approach, an efficient non-enzymatic glucose sensor based on pure phase of aurivillius bismuth molybdate (BM or γ-Bi₂MoO₆) mixed metal oxides is reported. Three BM samples were synthesized, with/without l-cysteine (Cys) and dodecylamine (DDA) as additives, leading to different shapes: bullet (BM-C), confetti (BM-2Cys) and candy (BM-2DDA). The morphology and purity of the structures were confirmed by FE-SEM images and XRD. In order to investigate the sensor application, the samples were integrated on reduced graphene oxide and incorporated into simple and inexpensive glassy carbon electrode (GCE) without using any polyvinylpyrrolidone (PVP) or Nafion. To perform cyclic voltammetry experiments, all three biosensors were measured in PBS solution (pH = 7) in ±1.5 voltage range and 50 mV s^-1 scan rate. Glucose identification by the synthesized composites is an obvious sign of their high efficiency. According to chronoamperomograms, the best sensitivity of 3050 μA L mmol^-1 cm^-2 with linear range of 0.02-0.14 mmol L^-1, low detection limit (LOD) of 0.004 mmol L^-1 and the signal/noise equal to 3 was achieved by BM-2DDA/rGO/GCE biosensor and its speedy amperometric response is less than 5 s. This biosensor showed impressive selectivity, repeatability and reproducibility results besides it maintains its stability considerably in great percentage of 98.5% after eight weeks. Also it showed prolonged stability after 50 min.

Keywords: Glucose; Mixed metal oxides; Non-enzymatic; Semiconductor; γ-Bi(2)MoO(6).