Toward the next generation of molecular imprinting with emphasis on the formation, by direct molding, of compounds with biological activity (biomimetics)

I would like to share with the participants the background and insights that made us work in what is now called molecular imprinting. In retrospect, for us it came as an intellectual byproduct from early studies on immobilized/entrapped enzymes and cells and that of affinity chromatography. As for the former aspect, once it was shown that enzymes could be entrapped in a gel matrix and remain active, the idea came up of whether it would be possible to subsequently remove the bio-catalyst, leaving a cavity (shape) behind, specific for rebinding the very same protein. As to the other aspect, that of bio-affinity chromatography, this gave us the insight that most biological interactions such as those between inhibitor and enzyme or antigen and antibody are non-covalent by nature. This is why in our studies trying to mimic these systems, we chose print (template) molecules and polymerizable monomers that will lead to non-covalent interactions. Combining these two principles (shape and functional complementarity) various specific imprints were prepared over the years, the properties of some of which (especially `plastibodiesʹ) will be discussed. Subsequently I intend to discuss research done in our laboratory over the last number of years with the goal of synthesizing directly on a bio-molecule such as an enzyme or cell, structures complementary for instance to the active site, e.g. by a polymerization process; a kind of direct molding. Examples of such studies with the aim of creating inhibitors, agonists or artificial competing affinity ligands will be given. Studies in these directions might contribute to what could be called the next generation of molecular imprints.