Magnetic molecularly imprinted polymer beads prepared by microwave heating for selective enrichment of b-agonists in pork and XXXX liver samples.

@entity1707 @entity38305 @entity7284 @entity1933 @entity16825
Novel magnetic molecularly imprinted polymer (MIP) beads using @entity38305 as template for use in extraction was developed by microwave heating initiated suspension polymerization. Microwave heating, as an alternative heating source, significantly accelerate the polymerization process. By incorporating magnetic @entity1933 , superparamagnetic composite MIP beads with average diameter of 80  m were obtained. The imprinted beads were then characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and vibrating sample magnetometer. Highly cross-linked porous surface and good magnetic property were observed. The adsorption isotherm modeling was performed by fitting the data to Freundlich isotherm model. The binding sites measured were 3.24  mol g(-1) and 1.17  mol g(-1) for the magnetic MIP beads and the corresponding non-imprinted magnetic beads, respectively. Cross-selectivity experiments showed the recognition ability of the magnetic MIP beads to analytes is relative to degree of molecular analogy to the template. Finally, this magnetic MIP bead was successfully used for enrichment of @entity38305 , @entity16825 and @entity7284 from ultrasonically extracted solution of pork and @entity1707 liver followed by high performance chromatography with fluorescence detection. The proposed method presented good linearity and the detection limits was 0.52-1.04 ng mL(-1).The recoveries were from 82.0% to 90.0% and from 80.4% to 86.8% for the spiked pork and @entity1707 liver, respectively, with the RSDs of 5.8-10.0%. Combination of the specific adsorption property of the MIP material and the magnetic separation provided a powerful analytical tool of simplicity, flexibility, and selectivity.
