Determination of Benzo[a]pyrene in Roast Meat by In Situ Growth of Covalent Organic Framework on Titanium Wire for Solid-Phase Microextraction Coupled with GC-FID

Benzo[a]pyrene (BaP) is a kind of trace pollutant commonly found in environment, food, and organism. It has been widely concerned because of its strong carcinogenicity to the human body. In this paper, covalent organic framework TpBD, in situ growth on titanium wire, was used as the coating of solid-phase microextraction (SPME) fiber and coupled with gas chromatography-flame ionization detector (GC-FID) for the detection of trace BaP in roast meat samples. The linear range of the developed method under the optimized experimental conditions was 0.02-15 mu g L-1, the detection limit (S/N = 3) was 0.006 mu g L-1, and the limit of quantification (S/N = 10) was 0.02 mu g L-1. The intra-day and inter-day precision of a single fiber were 1.73% and 2.27%, respectively. The relative standard deviation (RSD) between fiber-to-fiber was investigated by three as-fabricated fibers was 6.09%. Moreover, the enrichment factor of the fabricated TpBD SPME fiber for BaP was 4914, and the fiber can withstand at least 150 cycles of adsorption and desorption without significantly decrease in extraction efficiency (< 3.6%). Finally, the developed method was successfully applied to the detection of BaP in roast meat samples with the recoveries from 95.4 to 108.5%.