Evaluation of electrochemical behavior combined with the sensitive and selective determination of ceftriaxone using molecularly imprinted polymer-based sensor

Understanding the electrochemical behavior of antibiotic drugs could help develop sensors for selective and sensitive detection at trace levels due to their importance in food safety and environmental protection. In this work, we studied and evaluated the electrochemical behavior of ceftriaxone (CEF) using a bare glassy carbon electrode (GCE) as the first step. Differential pulse voltammetry and Cyclic voltammetry (CV) were used in this evaluation. CV showed that CEF has an oxidation peak at 0.926 V, while oxidation takes the best place in 0.1 M H2SO4 solution as an electrolyte. On the other hand, the relationship between Ep and pH showed an equal number of protons and electrons are involved in the oxidization process, while the slope value obtained from the equation plotted between logIp and logo (0.83) showed the diffusion-adsorption mix controlled oxidation of CEF. Using these conditions, CEF on GCE showed a linearity range between 1.0 x 10-7 and 7.5 x 10-6 M with LOD equal to 2.57 x 10-8 M. However, in order to increase the selectivity and sensitivity of GCE, a molecularly imprinted polymer (MIP)-based sensor was developed in the next part of this work. Herein, the photopolymerization technique was chosen to design the MIP on GCE using 4-amino benzoic acid (4-ABA) as a monomer. The LODs of the standard solutions and serum sample were 1.15 x 10-17 M and 1.19 x 10-17 M, respectively, while the linear range was between 1.0 x 10-16 and 1.0 x 10-15 M. Furthermore, interference effect evaluation and imprinting factor analysis were performed with selected interfering compounds and using cefuroxime, cefdinir, ceftazidime pentahydrate, cefazolin, and cefixime to demonstrate the sensor's selectivity. Moreover, the execution of the MIP sensor was confirmed by a non-imprinted polymer-based sensor. Finally, 4ABA/CEF@MIP-GCE was used to find out CEF in commercial serum and tap water samples precisely.