Rapid and Selective Cefuroxime Sensing via Gold Nanoparticle-Enhanced MIP-based Electrochemical Sensors

Cefuroxime (CFR), a second-generation cephalosporin antibiotic, is widely prescribed for the treatment of various bacterial infections due to its broad-spectrum antimicrobial activity. Accurate and sensitive quantification of CFR in biological and pharmaceutical matrices is crucial to ensure therapeutic efficacy and to prevent potential adverse effects. In this work, a molecularly imprinted polymer-based electrochemical sensor, enhanced with gold nanoparticles, was developed for the selective and ultrasensitive determination of CFR by electropolymerizing 1H-indazole-5-boronic acid as the functional monomer and aniline (ANI) as the co-monomer on a glassy carbon electrode. The incorporation of gold nanoparticles (AuNPs) significantly improved the sensor’s electrochemical performance by increasing the effective surface area and facilitating electron transfer. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and scanning electron microscopy (SEM) were used to confirm the successful formation of selective recognition sites and the sensor's functional integrity. Under optimized conditions, the developed molecularly imprinted polymer-based sensor exhibited excellent linearity over the concentration range of 1.00 × 10-11 M to 3.75 × 10-10 M, with a remarkably low limit of detection (LOD) of 1.59 × 10-12 M in standard solutions. Selectivity studies demonstrated that the sensor retained high specificity for CFR even in the presence of structurally related cephalosporins, including cefazolin, cefdinir, cefixime, ceftazidime, and ceftriaxone. Furthermore, the sensor's analytical applicability was successfully validated using biological samples and vial formulations containing injectable powder, confirming its robustness and practical utility.