Norfloxacin Fluorescent Probe for the Assessment of Cefepime in Biological Fluids and Pharmaceutical Formulation; Investigation of the Greenness and Blueness Characteristics.

In the present study, a norfloxacin (NFX) fluorescent probe was tailored for the spectrofluorometric measurement of cefepime (CFP). The proposed approach measured the quenching effect of CFP on the fluorescence intensity of NFX in acetate buffer solution. The obtained results show that CFP strongly quenches the fluorescence of NFX in a static mechanism. Under the optimal conditions, plotting the fluorescence quenching values (∆F) against CFP concentrations resulted in two ranges varying from 0.8 to 28 μg/mL (r² = 0.9979) and from 40 to 92 μg/mL (r² = 0.9929). Furthermore, the limits of quantification and detection were 2.0526 and 0.6773 μg/mL, respectively. In terms of intra- and inter-day recorded precisions (n = 5), the % RSD ranged between 0.31% and 0.6% and 0.55% and 1.02%, respectively. Additionally, practicality/applicability and the green feature of the new method were considered by BAGI and AGREE automated approaches. The new spectrofluorometric approach was positively applied for the quantification of CFP in injection powder and spiked biological fluids, including spiked human urine and plasma samples. According to previously published fluorescence methods, the present method is considered the first fluorescence one for the assay of CFP in human biological fluids with accurate and precise results.