Green analytical methods for quantification of a new combination therapy for amyotrophic lateral sclerosis:...

Amyotrophic lateral sclerosis is a progressive neurodegenerative disorder characterized by the degeneration of upper and lower motor neurons, leading to progressive muscle weakness, paralysis, and respiratory failure. The recently proposed combination therapy consisting of celecoxib and ciprofloxacin hydrochloride has emerged as a potential treatment for amyotrophic lateral sclerosis and other neurodegenerative disorders. The present study aimed to develop and validate simple, sensitive, environmentally friendly, and cost-effective analytical methods for the simultaneous determination of celecoxib and ciprofloxacin hydrochloride in bulk powders, laboratory-prepared tablets and plasma. Two ultraviolet spectrophotometric methods were established. The first method relies on direct absorbance measurements of ciprofloxacin hydrochloride at 318 nm and celecoxib at the isosbestic point at 266 nm, while the second one employs first-derivative ratio spectrophotometry for the selective determination of ciprofloxacin hydrochloride and celecoxib at 280 nm and 254 nm, respectively. Moreover, a reversed-phase high-performance liquid chromatographic method was developed using a C18 stationary phase, an optimized mobile phase composition and both diode array and fluorescence detectors, achieving efficient separation and accurate quantification of both analytes. The developed procedures were successfully applied to laboratory-prepared tablets and plasma following optimization of the sample preparation protocol to minimize matrix interference and to improve analytes recovery. Validation results showed excellent linearity over the investigated concentration ranges together with satisfactory accuracy, precision, selectivity, and sensitivity, confirming the reliability of the proposed methods for routine quality control and bioanalytical applications. The overall analytical performance and environmental sustainability of the developed methods were further assessed using the environmental performance and practicality Index framework, demonstrating their suitability as reliable and sustainable analytical approaches for the determination of celecoxib and ciprofloxacin hydrochloride.