Preparation And Application Research Of Molecularly Imprinted Polymers Of The Patulin

Patulin [4-hydroxy-4H-furo[3,2-c]pyran-2(6H)-one] is a naturally occurring toxic and carcinogenic secondary metabolite produced by a variety of species, particularly Penicillium, Aspergillus and Brysochylamys. Studies have confirmed that Patulin is a neurotoxin with potentially carcinogenic and mutagenic type. In recent years, the pollution from patulin has attracted the attention of many countries and international organizations and stipulated the maximum limit in food. Therefore, the detection of trace patulin has become a hot research. Several analytical methods have been reported to detect Patulin, including microbiological method, thin-layer chromatography, gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography-UV detection (HPLC-UV), liquid chromatography-mass spectrometry (LC-MS) and micellar electrokinetic capillary chromatography (MEKC). Because of its volatility and strong adsorption spectrum, LC-UV has been the most widely applied techniques for Pat determination. However, the poor resolution of UV detection is observed between Pat and other interfering substances especially5-hydroxymethyl furaldehyde (hydroxymethylfurfural (HMF)), Therefore, it is necessary to establish an accurate and efficient method for highly selective analysis of Pat in foods.In this study, a novel molecularly imprinted silica-gel microsphere was synthesized using oxindle as template instead of patulin,3-aminopropyltriethoxysilane as functional monomer, activated silica gel as the support material, and tetraethoxysilicane as cross-linker by surface molecular imprinting technique in combination with a sol-gel process. The imprinted materials were employed as sorbent of online solid-phase to determine patulin in food by HPLC. The synthesis conditions were optimized and the prepared MIPs were characterized using FT-IR spectroscopy, scanning electron microscopy, and the adsorption properties including adsorption equilibrium, kinetics and selectivity experiments. The MIP has shown excellent affinity and high selectivity adsorption to Pat and displayed a fast kinetics. The adsorption capacity to Pat and HMF were1.657mg g"1and0.406mg g"1, respectively. The parameters of online-SPE-HPLC including the pH of loading sample, the loading rate and eluting time were optimized. The enrichment factor and the minimum detection limit (S/N=3) are125and0.50μg L-1,respectively. The linear range (R2=0.9990) is2-40μg L-1, and the precision of peak area (relative standard deviation, RSD) for nine consecutive enrichment was7.80%.The sample apple juice, pear juice, haw juice and haw flakes in Tianjin market at the spiked concentrations of20μg kg-1,40μg kg-1,60μg kg-1were detected using online-SPE-HPLC method to validate the application capability and satisfactory results with Pat recoveries of60.13%-97.60%were obtained, signifying the developed method could be used for.