Covalent Organic Framework/Polyacrylonitrile Electrospun Nanofiber for Dispersive Solid-Phase Extraction of Trace Quinolones in Food Samples.

The extraction of quinolone antibiotics (QAs) is crucial for the environment and human health. In this work, polyacrylonitrile (PAN)/covalent organic framework TpPa-1 nanofiber was prepared by an electrospinning technique and used as an adsorbent for dispersive solid-phase extraction (dSPE) of five QAs in the honey and pork. The morphology and structure of the adsorbent were characterized, and the extraction and desorption conditions for the targeted analytes were optimized. Under the optimal conditions, a sensitive method was developed by using PAN/TpPa-1 nanofiber as an adsorbent coupled with high-performance liquid chromatography (HPLC) for five QAs detection. It offered good linearity in the ranges of 0.5-200 ng·mL for pefloxacin, enrofloxacin, and orbifloxacin, and of 1-200 ng·mL for norfloxacin and sarafloxacin with correlation coefficients above 0.9946. The limits of detection (S/N = 3) of five QAs ranged from 0.03 to 0.133 ng·mL. The intra-day and inter-day relative standard deviations of the five QAs with the spiked concentration of 50 ng·mL were 2.8-4.0 and 3.0-8.8, respectively. The recoveries of five QAs in the honey and pork samples were 81.6-119.7%, which proved that the proposed method has great potential for the efficient extraction and determination of QAs in complex samples.