Micellar HPLC and UV Methods with Time Programming for Synchronically Quantifying Gatifloxacin and Its Preservative in Eye Drops: Appraisal of Ecological Impact

Modern society is increasingly reliant on sustainable solutions. We suggest a creative study that meets the standards of sustainability in analytical chemistry. The objective is to promote eco-friendly methods for concurrently detecting Gatifloxacin (GAT) and benzalkonium chloride (BEN) in ocular solutions. Using a sustained mobile phase flow rate of 0.8 mL/min^-1 and acidic water: 10% 1-butanol in water (40:60, v/v), GAT was retained for 2.242 min at 287 nm, followed by BEN homologues at 215 nm for the next 2.982 and 4.201 min. This process was simple, quick, and precise. The method demonstrated peak symmetry, low processing times, good resolution, and correlation values 0.999. For GAT, the linearity ranged from 0.001 to 0.023 mgmL^-1, while for BEN, it was from 0.003 to 0.060 mgmL^-1 in the HPLC system, while the UV method in the range of 0.005-0.03 mgmL^-1 for all drugs. A unique feature of this study is the integration of multiple sustainability assessment tools, such as AGREE, AGREEprep, ComplexGAPI, ESA, BAGI, and NEMI pictograms, providing an exhaustive appraisal of the methods' environmental impact and enhancing the robustness of the findings. In addition, eco-friendly and cost-effective alternatives were explored using water as the solvent in complementary spectrophotometric procedures such as mean centering of ratio spectra (MCR). Each technique showed respectable accuracy and precision (RSD ≤ 2%) and high linearity r² > 0.9990. The proposed methodologies provide inexpensive, eco-friendly alternatives to conventional approaches, promoting a less harmful future for quality control and moving analytical chemistry closer to more sustainable methods.