Biomimetic ciprofloxacin sensors made of molecularly imprinted network receptors for potential measurements

Abstract

A molecularly imprinted polymer (MIP), with special molecule recognition properties of ciprofloxacin CIP), was prepared by thermal polymerization in which ciprofloxacin acted as the template molecule, methacrylic acid (MAA), acrylonitrile (AN) and 2-vinylpyridine (2-VP) acted as the functional monomer and ethylene glycol dimethacrylate (EGDMA) acted as the crosslinker. A biomimetic potentiometric field monitoring device was developed for the assessment of cirofloxacin (CIP) antibiotics based on these newly synthezised imprinted polymers. The sensing elements were fabricated by the inclusion of CIP imprinted polymers in polyvinyl chloride (PVC) matrix. The sensors showed a high selectivity and a sensitive response to the template in an aqueous system. Electrochemical evaluation of these sensors revealed near-Nernstian response with slopes of 29.9 ± 0.7, 27.9 ± 0.5, and 30.3 ± 0.8 mV decade⁻¹ with a detection limit 41.3, 46.3, and 32 μg mL⁻¹CIP with MIP/MAA, MIP/2-VP and MIP/AN membrane based sensors plasticized with DOP, respectively. The effects of lipophilic salts and various foreign common ions were tested. The sensors were easily used in a single channel flow injection system and compared with a tubular detector. The intrinsic characteristics of the detectors in a low dispersion manifold were determined and compared with data obtained under a hydrodynamic mode of operation. Significantly improved accuracy, precision, response time, stability, selectivity and sensitivity were offered by these simple and cost-effective potentiometric sensors compared with other standard techniques. The method had the requisite accuracy, sensitivity and precision to assay CIP in pharmaceutical formulations and biological fluids.