Beyond natural antibodies - a new generation of synthetic antibodies created by post-imprinting modification of molecularly imprinted polymers.

The molecular imprinting technology yields artificial materials capable of antibody-like molecular recognition. Molecularly imprinted materials are attractive because procedures for their preparation and use are comparatively simple. The number of research reports concerning molecularly imprinted polymers (MIPs) have been increasing yearly, attracting a great deal of interest in various fields. However, as most MIPs have been generated by relatively simple methods developed from the 1970s to the 2000s, resulting in MIPs bearing a single function, their capabilities are limited compared to those of multi-functionalised naturally occurring materials. Proteins are biosynthesised through multiple steps, including fabrication of peptide backbone and subsequent post-translational modifications that introduce additional functionalities, finally producing the mature protein. Post-imprinting modification (PIM) is an innovative strategy for generating MIPs analogous to biosynthetic proteins. New functionalities are introduced, in a site-directed manner, into a molecular imprinted cavity. Monomer residues in the cavity are chemically modified to incorporate new features, such as on/off switching of binding activity, fluorescence signalling, photoresponsivity, and finely tuned binding characteristics. In this Feature Article, we provide an overview of multifunctional MIPs prepared via PIMs developed earlier and the currently used state-of-the-art ones.