Microextraction of selective serotonin reuptake inhibitors from urine using poly(ethylene-co-vinyl acetate) coated paper-based sorptive phase: giving a new use to conventional materials

Reusing polymer residues for synthesizing new sorptive phases is a relevant research topic in sample preparation that is in line with sustainability and affordability concepts. It allows giving an alternative use to chemical residues and permits the preparation of cost-effective sorbents. In this article, poly(ethylene- co -vinyl acetate) residues are employed for preparing a paper-based sorptive phase by the dip coating technique. The PSP is used to extract selective serotonin reuptake inhibitors (namely, sertraline, paroxetine, and fluoxetine) from urine samples using liquid chromatography coupled with mass spectrometry for the final determination. The different variables affecting the synthesis (polymer concentration and number of dips) and the extraction (pH, ionic strength, sample volume, and extraction time) have been evaluated using blank urine samples spiked with the analytes. The proposed method has been validated, obtaining limits of detection lower than 0.3 μg L −1 , linear range from 1 to 600 μg L −1 (R 2 > 0.999), intra-day and inter-day precision better than 8.4 and 19.0 %, respectively, and intra-day and inter-day accuracy values ranging from 88.8 to101.1 and from 96.3 to 108.1 %. Three different urine samples from patients under paroxetine and fluoxetine treatment were analyzed, obtaining concentrations within the linear range in all cases. • A sorbent composed of paper and poly(ethylene- co -vinyl acetate) is presented. • Three selective serotonin reuptake inhibitors are extracted from urine samples. • A high throughput microextraction procedure coupled to LC-MS/MS is proposed. • The analysis of samples from patients under therapeutic treatment was carried out.