Multi-walled carbon nanotubes/polyaniline covalently attached 18-crown-6-ether as a polymeric material for the potentiometric determination of delafloxacin

In recent years, the global emergence of antibacterial resistance has led to the development of new antibacterial drugs with unique chemical structures. The FDA has recently approved delafloxacin for acute bacterial infection treatment. The proposed potentiometric sensor is considered as the first electrochemical method for accurate, precise, and sensitive determination of delafloxacin. It was based on developing a novel polymeric material that functioned as a recognition element and a transducer at the same time. This polymeric material was fabricated by the covalent polymerization of aniline monomers with the crown ether ionophore and followed by the ionic attachment to the surface of the MWCNTs. A linear response ranging from 1 × 10–3 to 1 × 10–8 mol L−1 and a high sensitivity reached nano-molar level down to 3.5 × 10–9 mol L−1 have been displayed by the fabricated sensor. It was used efficiently in human plasma, pure form, and pharmaceutical tablets for the quantitation of delafloxacin with high recovery ranged from 97.68% to 100.45% and without any extraction or pretreatment steps. The proposed sensor is characterized by high selectivity and stability over 143 days with no surface renewal.