Enrichment of tetracycline residues from honey samples using carrier‐mediated hollow fibre liquid‐phase micro‐extraction and quantification by LC‐Q‐TOF/MS

Abstract

BACKGROUND In this study, development and validation of a simple, miniaturized and, environmentally friendly carrier‐mediated three‐phase hollow‐fibre liquid‐phase micro‐extraction (HFLPME) technique was investigated for the enrichment of tetracycline residues in honey samples. The extracts were analysed using UV–visible spectrophotometry and liquid chromatography–quadrupole time‐of‐flight mass spectrometry (LC‐Q‐TOF/MS). Parameters affecting the extraction efficiency of HFLPME such as pH of the donor and acceptor solutions, salt addition, agitation speed and extraction time were optimized. RESULTS The calibration curves showed good linearity, in the range of 1–100 μg kg−1 with correlation coefficients ranging between 0.9943 and 0.9992, under the optimized conditions. Recoveries of blank honey samples at three spiking levels (1, 10 and 20 μg kg−1) ranged from 81.2% to 107.5%. Relative standard deviations for the precision of the method were less than 15.0%. Limits of detection and limits of quantification were in the range of 0.0861–0.2628 μg kg−1 and 0.2610–0.7964 μg kg−1, respectively. Finally, the proposed method was successfully applied in the extraction of five tetracyclines from honey samples. Doxycycline residue detected in one of the commercial honey samples was below the limit of quantification. CONCLUSION Because of the advantages offered by HFLPME, this method can be employed as an alternative to conventional extraction techniques for the clean‐up and pre‐concentration of antibiotics in complex matrices, including food samples. © 2021 Society of Chemical Industry

Magnetic covalent organic frameworks for rapid solid-phase extraction of phthalate esters and bisphenol A in beverage samples

“…This may be because the addition of NaCl seems to increase the ionic strength of the solution and helps to reduce the solubility of the targets, thus promoting the migration of the targets to the acceptor phase. 28,29 Therefore, 2% w/v was selected as the optimal NaCl concentration.…”