Rapid, green and semi-automated PT-μSPE for antidepressants analysis in urine and plasma using melt-blown polypropylene from disposable face masks as sorbent

Extracting antidepressants from biological samples is challenging due to their low concentrations and complex matrices. Pipette-tip solid-phase microextraction (PT-μSPE) simplifies the process, reducing solvent use and enabling automation, but challenges like custom adsorbents and toxic solvents limit its broader application. Melt-blown polypropylene nonwoven, sourced from the middle layer of 3-ply disposable non-woven face masks, was employed as the sorbent material. The extraction tip was easily assembled by combining a 200 μL pipette tip, the melt-blown polypropylene nonwoven, and a 1 mL pipette tip. This method provides a cost-effective and sustainable alternative to conventional adsorbents. A 90% ethanol solution was selected as the desorption solvent to comply with green chemistry principles, with the volume minimized to 100 μL to reduce waste. The pH adjustment was achieved using low-toxicity sodium carbonate (Na₂CO₃). The developed PT-μSPE method proved excellent linearity, sensitivity, accuracy, precision, and robustness, making it suitable for routine antidepressant monitoring in plasma and urine. It offers a practical, scalable, and environmentally friendly solution for therapeutic drug monitoring.