Development of an ecofriendly dispersive liquid phase microextraction method for the preconcentration of β-blockers in waste and environmental samples

Abstract

Effective sample preparation is crucial in instrumental analysis to enhance selectivity, sensitivity, and instrument protection. The current trend of miniaturization in liquid–liquid extraction aims to conserve solvents and promote environmental sustainability. Liquid phase microextraction, requiring only small volumes of the extractant, facilitates sample preconcentration without the need for evaporation and reconstitution. This study presents the development of an eco-friendly dispersive liquid–liquid microextraction method employing solidification of floating organic droplets for the determination of five β-blocker drugs in waste and environmental samples. The optimization of key variables affecting extraction efficiency, including extractant type and volume, pH of the diluent, dispersion technique, vortexing, and centrifugation time, was carried out. Optimal results were achieved using 50 μL of dodecanol as the extractant, 1 min of vortexing for dispersion, followed by 2 min of centrifugation for phase separation. The sample was then subjected to a 5 min cooling in an ice bath to solidify the dodecanol before UHPLC/UV analysis. The method yielded enrichment factors within the range of 23–55. The applicability of this approach was demonstrated in laboratory waste and environmental water analysis, with acceptable % recoveries ranging from 98.07 % to 101.83 % and %RSD below 1.96. Moreover, we assessed the method’s performance and greenness with ComplexGAPI, BAGI, and carbon footprint. This method not only provides high efficiency and reliability but also aligns with the principles of sustainablility.