Eco-friendly, sensitive and inventive first derivative synchronous spectrofluorimetric determination of ciprofloxacin and phenylephrine in their pure form, single and combined eye drops.

A facile, sensitive, accurate and green spectrofluorimetric method was evolved for the assay of ciprofloxacin hydrochloride (CFX) and phenylephrine hydrochloride (PLN) in their co-formulated eye drops with their challengeable ratio of 30:1 for CFX and PLN, respectively. Such drops are clinically used for the treatment of eye bacterial infections. They relieve the symptoms of infection by stopping further growth of the causative microorganisms. The assay principle based on first-order synchronous spectrofluorometric scan using Δ λ = 40 nm in which PLN peak amplitudes were recorded at 283.4 nm, meanwhile CFX was measured at 326.2 nm in the same scans. The calibration curves were linear within the concentration ranges: 0.02-0.5 µg/mL and 0.5-5.0 µg/mL for PLN and CFX, respectively. The method validation was confirmed following the International Conference of Harmonization (ICH) Guidelines. This suggested method was the first one that described simultaneous analysis of PLN and CFX by a spectrofluorimetric technique. In this method, green analytical procedures were implemented to lessen occupational and environmental perils and method greenness was assessed by four assessment tools. GAPI, NEMI, AGREE and Analytical eco-scale were applied to this study and it was deduced from their results that the method had high degree of greenness as it fulfilled all requirements of GAPI, NEMI pictograms and it had high scores of analytical eco scale (97) and AGREE methods (0.82). Subsequently, it was successfully applied to assay both drugs in pure forms, pharmaceutical single and co-formulated eye drops.