No abstract

No abstract

Synthetic materials capable of recognizing proteins are important in separation, biosensors and biomaterials. In this study, bovine serum albumin-imprinted soft-wet polyacrylamide gel beads were prepared via inverse-phase suspension polymerization, using acrylamide and N,N'-methylene diacrylamide as polymeric matrix components and methacrylic acid as functional monomer. The adsorption study showed, through the imprinting process, that the imprinted gel beads had much higher adsorption capacity than the nonimprinted gel beads, and that the matching of the surface zeta-potential between the templates and the imprinted gel beads can enhance the imprinting effect. Adsorption kinetics indicated that the adsorption process could be described as an apparent first-order kinetic process for the gel beads. From the adsorption isotherm curve, we found that the adsorption of the imprinted gel beads was in agreement with the Langmuir adsorption model. Moreover, selectivity testing of the imprinted gel beads showed that imprinted gel beads exhibited good recognition for BSA as compared to the control protein. We speculate that the formation of complementary shapes and multiple-point electrostatic interactions between the imprinting cavities and the template proteins are the two factors that lead to the imprinting effect.

Tyrosine and phenylalanine imprinted Fe 3 O 4 /P(St-DVB) composite beads with magnetic susceptibility were prepared by suspension polymerization using Fe 3 O 4 as the magnetically susceptible component, methacrylic acid and acrylamide as functional monomers, styrene and divinylbenzene as polymeric matrix components, stearic acid as porogen, and poly(ethylene glycol) 4000 as dispersant. Scanning electron microscopy examination of the composite beads showed macropores on the surface of spherical beads. The diameters of the composite beads and the macropores were in the ranges ϳ 400 -450 and 4 -20 m, respectively. The average content of Fe 3 O 4 inside the composite beads was 3.78%, and Fe 3 O 4 was unevenly distributed. The mechanism of macropore formation and the concept of "intellectual cavity" of molecularly imprinted composite beads were proposed. The recognition selectivity of the composite beads was investigated using tyrosine and phenylalanine as both templates and comparative molecules. Tyrosine-imprinted composite beads exhibited a good recognition selectivity for tyrosine, and the separation factor was up to 3.67. In contrast, phenylalanineimprinted composite beads had little recognition selectivity for phenylalanine and the separation factor was only 1.12. It was confirmed that the three-site interaction between tyrosine and functional monomers was stronger than the twosite interaction between phenylalanine and functional monomers.

No abstract