Preparation and recognition performance of uric acid-imprinted material prepared with novel surface imprinting technique

Acrylonitrile (AN) was first graft-polymerized on the surfaces of crosslinked polyvinyl alcohol (CPVA) microspheres by initiating of cerium salt, and then the grafted polyacrylonitrile (PAN) was transformed to polyamidoxime (PAO) via amidoximation transform reaction, resulting in the functional microspheres PAO/CPVA. By adopting the novel surface-molecular imprinting technique put forward by us, uric acid molecule-imprinted material MIP-PAO/CPVA was prepared with glutaraldehyde as crosslinking agent The binding character of MIP-PAO/CPVA towards uric acid was investigated in depth with both batch and column methods and using guanine as a contrast substance whose chemical structure is similar to uric acid to a certain extent. The experimental results show that the surface imprinted material MIP-PAO/CPVA has excellent binding affinity (a great binding capacity of 104 mg/g) and high recognition selectivity for the template molecule, uric acid. The selectivity coefficient of PAO/CPVA microspheres (non-imprinted material) for uric acid relative to guanine is only 1.273, displaying no recognition selectivity for uric acid. However, after imprinting, the selectivity coefficient of MIP-PAO/CPVA for uric acid in respect to guanine is remarkably enhanced to 14.00, displaying the excellent recognition selectivity and binding affinity towards uric acid molecules.