Enantioselective Determination of Duvelisib in Wastewater Samples by Electrokinetic Chromatography after µSPEed Preconcentration

The development of sensitive and selective analytical methodologies for the determination of chiral drugs in complex matrices is of increasing importance in pharmaceutical, clinical, and environmental analysis. Duvelisib is a chiral anticancer drug marketed as the pure S-enantiomer [1], and its determination in environmental samples requires efficient preconcentration due to the low concentration levels expected in these matrices. In this work, a miniaturized solid-phase extraction procedure based on µSPEed technology was developed and combined with Electrokinetic Chromatography (EKC) for the enantioselective determination of duvelisib in wastewater samples.

The extraction procedure, based on previous works of our research group [2,3], was optimized using PS/DVB-RP µSPEed cartridges. The cartridges were conditioned with methanol and equilibrated with water before sample loading. Wastewater samples were then extracted, followed by elution with methanol, solvent evaporation, and reconstitution in the background electrolyte (BGE) prior to EKC analysis. The enantiomeric separation was achieved using sulfobutylated-β-cyclodextrin as chiral selector in 25 mM formate buffer (pH 3.0) at 30 ℃ and an applied voltage of −30 kV, allowing the rapid and efficient separation of both duvelisib enantiomers in 5.1 min and with an enantiomeric resolution of 3.1.

The proposed methodology showed satisfactory analytical performance. Extraction recoveries that included 100% for both enantiomers were obtained. Good linearity was achieved, with correlation coefficients higher than 99.3%, while precision values were satisfactory in terms of migration times and corrected peak areas (lower than 1.5% and 6.9%, respectively). Detection limits were in the low µg L⁻¹ range. In addition, no significant matrix interferences were observed after the µSPEed procedure.

The developed µSPEed-chiral EKC methodology provides a rapid, efficient, semiautomatic, and environmentally friendly strategy for the enantioselective determination of duvelisib in wastewater samples, improving sensitivity while reducing solvent consumption and sample handling according to the principles of green analytical chemistry.