Thin-film solid-phase microextraction of pesticides from cereal samples using electrospun polyvinyl alcohol/modified chitosan/porous organic framework nanofibers

In this study, a coating of electrospun polyvinyl alcohol/modified chitosan/hydroxy-containing porous organic framework (PVA/MCS/HC-POF) was fabricated and applied as a novel sorbent for thin-film solid -phase microextraction of pesticides from cereal samples, followed by HPLC-UV. The successful fabrication of PVA/MCS/HCPOF was confirmed through characterization tests. The functional group of MCS and a large number of hydroxyl groups on the HC-POF structure contributed to the co -extraction of pesticides. Under the optimum conditions, the calibration plots were linear within the range of 5.0-800 ng mL-1 (r2 >= 0.978), and the limits of detection were obtained below 4.0 ng mL-1. The method's precision was investigated through intra-day, inter-day, and film -to -film RSD (%) measurements, all of which were less than 6.5 %, 8.2 %, and 10.0 %, respectively. Furthermore, satisfactory recoveries ranging from 63.3 % to 79.0 % were obtained. Accordingly, the proposed method can be considered a suitable alternative for measuring trace amounts of pesticides in cereal samples.