Sensitive Voltammetric Amoxicillin Sensor Based on TiO₂ Sol Modified by CMK‐3‐type Mesoporous Carbon and Gold Ganoparticles

Abstract

Abstract In this work, a novel voltammetric sensor was developed to determine amoxicillin (AMX). The electrode modification layer consisted of titanium dioxide sol (TiO 2 ) modified with gold nanoparticles (AuNPs), CMK‐3‐type mesoporous carbon and Nafion. The morphology of the electrode composite was studied by scanning electron microscopy (SEM). Electrochemical behaviour of AMX at proposed electrode was studied. Effects of parameters comprising the amount of CMK‐3 and AuNPs in matrix composite, pH of supporting electrolyte and incubation time on the sensitivity of developed sensor were examined. The analytical characteristics of the proposed sensor were assessed. The developed sensor exhibited linear response in two AMX concentration ranges: from 0.5 to 2.5 μM and from 2.5 to 133.0 μM, with sensitivity of 1420 μA mM −1 (5071 μA mM −1 cm −2 ) and 832 μA mM −1 (2971 μA mM −1 cm −2 ), respectively. The detection limit was evaluated as 0.3 μM. For verification purposes the sensor was successfully employed in determination of AMX in pharmaceutical product, mineral and environmental water using a flow‐batch monosegmented sequential injection approach.