Preparation of graphene oxide and its application for improving the properties of an electrochemical sensor for the determination of bambuterol hydrochloride in real samples

Abstract

In this study, an ion-selective electrode modified with graphene oxide (GO) was developed to determine bambuterol hydrochloride (BAM) via an electrochemical method. First, a composite of the electro-active complex and GO was prepared as a complex containing GO, BAM and sodium tetraphenylboron (GO@BAM–TPB) via a drop-by-drop operation under stirring. In the next step, a membrane solution for the electrode was made by mixing GO@BAM–TPB and film-forming materials, and the as-prepared membrane solution was dripped uniformly onto the surface of a bare platinum electrode. A few days later, the modified electrode was dried at room temperature and was reserved for use. The structure and morphology of materials and the electrochemical properties of the modified electrode were characterised adequately. We have discussed the outcomes of modifications in both structure and morphology aspects. Compared with traditional electrodes, the parameters of the modified electrode were as follows: a lower LOD (3.4 × 10⁻⁷ mol L⁻¹), a wider response range (1.0 × 10⁻¹ to 1.0 × 10⁻⁶ mol L⁻¹), and a shorter response time (15 s). Moreover, this modified electrode exhibited good selectivity, reproducibility, long lifetime (up to 12 weeks) and wide pH range (3.5–7.1). Finally, the BAM selective electrode was employed for determining BAM in real samples (e.g., swine urine), and it was proved to be a reasonable method for the determination of BAM.