Polycatechol coated cigarette filter as a sorbent for microextraction by packed sorbent of acidic non-steroidal anti-inflammatory drugs (NSAIDs) from wastewater samples

In this study, we employed microextraction by packed sorbent (MEPS) using polycatechol-coated cigarette filters (PCCFs) as a sorbent to extract acidic non-steroidal anti-inflammatory drugs (NSAIDs) from water samples, followed by high-performance liquid chromatographic analysis. The formation of coating on cigarette filter was confirmed by Fourier transform infrared (FT-IR) spectroscopy, UV–vis diffuse reflectance spectroscopy (DRS) and scanning electron microscopy (SEM). The effect of coating parameters on extraction efficiency of acidic NASIDs were investigated and 106.0 mg of Na₂CO₃, 30.0 mg of catechol and 3 h coating time were selected as optimum conditions. Additionally, other factors affecting the analyte extraction efficiency were optimized including a sample solution pH of 2.0, 700.0 µL of methanol as the elution solvent, 3 sorption cycles, 2 desorption cycles, and a 1.5 ml sample volume. Under the optimum conditions the calibration curves for all three analytes were draw and the analytical performance parameters including linear dynamic range (50.0–1000.0 µg.L⁻¹ for naproxen and diclofenac and 100.0–500.0 µg.L⁻¹ for ibuprofen) with R² > 0.9982, limit of detection (LOD < 45.3 µg.L⁻¹), precision (RSD% < 6.5), accuracy (recovery% > 90.1) and enrichment factor (EF > 2.7) were evaluated. Finally, this method was successfully used to extract and determine the amount of selected acidic NSAIDs in wastewater samples. The sorbent was cheap, easily prepared, efficient, and even reusable.