Complex functional materials consisting of bioactive molecules immobilized on solid supports present potential applications in
biosensoring. Advances in the fabrication of these surface materials are of growing interest for antibody-based diagnosis. This work exploits
dendrimers as versatile nanostructures for templating sensor surfaces and the critical role of the immobilization protocol in the
solid supports cellulose and zeolites, of organic and inorganic composition respectively. The fabrication and characterization, including
the degree of functionalization and reproducibility, of different nanostructured materials are described. To validate the approach, the fabricated
supports were further used as a solid phase for developing a radioimmunoassay to detect immunoglobulin E (IgE) specific to
penicillin, the antibody involved in immediate allergy responses to this drug. The dendrimer-modified supports provide assays with significantly
enhanced sensitivity, as well as increase the availability of biomolecules for specific interaction and minimize nonspecific adsorptions
through appropriate functionalization protocols in each case. The manufacturing methodology involved the use of a long, flexible
hydrophilic spacer in the cellulose materials, and a higher surface density of the immobilized dendrimers in the zeolite crystals. The
ability of hybrid zeolite materials in such biosensing applications was evaluated for the first time. The assays were validated in human serum
samples from patients allergic to penicillin and from non-allergic controls. The specificity and improved sensitivity of the dendrimer-
modified supports make these strategies versatile for different bioactive molecules and could have significant implications for the
quantification of a wide range of specific IgE antibodies and other biomolecules of diagnostic interest.
