Simultaneous enrichment and analysis of benzimidazole by in-tube SPME-MS based on poly (3-Acrylamidophenylboronic acid-co-divinylbenzene-co-N,N'-methylenebisacrylamide) monolithic column.

In this work, a sensitive, rapid, and matrix effect-free method for online simultaneous detection of benzimidazoles in animal products by in-tube solid-phase microextraction coupled with mass spectrometry (in-tube SPME-MS) was investigated. Herein, according to the chemical structures properites of the analyte benzimidazoles, poly (3-Acrylamidophenylboronic acid-co-divinylbenzene-co-N,N'-Methylenebisacryladmide) [poly (AAPBA-co-DVB-co-MBAA)] microextraction column was prepared, and severs as the extraction and enrichment medium (in-tube SPME) via hydrophobic, B-N coordination, π-π, and hydrogen bonding interactions with the benzimidazoles. The monolithic column was optimized and characterized, showing satisfactory permeability and extraction capacity in range of 514-1000 μg mL-1 for the benzimidazoles. The important parameters of the in-tube SPME-MS system experimental condition were systematically optimized to achieve the maximal extraction efficiency. Under the optimized condition, the MS intensity of benzimidazoles measured by in-tube SPME-MS is more significant, cleaner, and has a better signal-to-noise ratio than the mass intensity measured by direct MS method. Good linearity was obtained with correlation coefficients between 0.9915 and 0.9990, and the detection limits (S/N = 3) of the benzimidazoles were between 0.55 and 0.91 ng g-1. Recoveries in the range of 72.5%-92.4% were obtained for the benzimidazoles in pork and chicken in three spiked concentration levels, with satisfactory relative standard deviations (n = 4) that lower than 7.5%. The developed in-tube SPME-MS method based on the poly (AAPBA-co-DVB-co-MBAA) column was successfully used to sensitively determine trace benzimidazoles in animal products without interference peaks, indicating that it is promising for the analysis of benzimidazoles in practical samples that requiring minimal sample pre-treatment and no chromatographic separation.