Imprinting effect of protein-imprinted polymers composed of chitosan and polyacrylamide: a re-examination.

In this paper the imprinting effects recently reported with protein-imprinted polymers based on chitosan and polyacrylamide are re-assessed. Molecularly imprinted polymers (MIPs) from which the embedded template molecules were removed by washing with a solution of sodium dodecyl sulfate and acetic acid were prepared. In batch template rebinding experiments, the MIPs displayed quite high template binding capacity as reported previously. However, the non-imprinted polymers (NIPs), after washing with the same solution, also showed large binding capacity nearly equal to that of the MIPs. X-ray diffraction and scanning electronic microscope investigations confirmed remarkable property changes of the NIPs after the washing process. These findings indicate that the non-specific adsorption resulting from the template removing process rather than the imprinted sites generated on the MIPs themselves may account for the high template rebinding capacity of the reported protein-imprinted polymers.