Renewable enzyme reactors based on beds of artificial gel antibodies

A novel approach is described for the synthesis of beds for enzyme reactors. The method is based on the use of artificial antibodies in the form of polyacrylamide gel particles with diameters around 0.1-0.3 mm. These gel particles mimic protein antibodies, raised in experimental animals, in the sense that they selectively recognize and adsorb only the protein present during the preparation of the antibodies. The gel antibodies have several advantages over conventional protein antibodies, which can be taken advantage of in the design of enzyme reactors; for instance, if upon prolonged use the immobilized enzyme loses its activity it can easily be replaced by an active enzyme, which is not possible when the enzyme is immobilized via a conventional protein antibody (a new bed with immobilized protein antibodies must be prepared); and equally or more remarkable: the enzyme can be applied in the form of a non-purified extract since the selectivity of the artificial gel antibodies is so high that they will fish-out the enzyme, but no other proteins in the extract. In addition, no preconcentration of the enzyme solution is required prior to the immobilization, since the enzyme is enriched at the top of the column upon the application. These unique properties make enzyme reactors based on artificial gel antibodies very attractive, also in process chromatography. The potential application range of the artificial gel antibodies is enormous since the same method for their synthesis can be used independent of the structure and the size of the antigen; for instance, renewable biosensors based on gel antibodies for the selective detection of protein biomarkers, as well as pathogenic viruses, bacteria, and spores (for instance Anthrax) should not be difficult to design. (c) 2008 Elsevier B.V. All rights reserved.