Immobilization of Protein Probes on Biochips with Brush Polymer Cells

Objective: The biochip method allows microscale multiparametric analysis of macromolecular samples using a matrix of immobilized molecular probes. Selection of materials for biochip fabrication, functionalization of the carrier surface, and the method of immobilization of molecular probes are the key tasks of biochip technology. Methods: Methods of obtaining polymer coating from polyvinyl acetate on the surface of polyethylene terephthalate polymer substrates and subsequent production of brush polymers by photoinduced radical copolymerization of acrylate monomers have been studied. Cell matrices with numerous reactive chemical groups for subsequent immobilization of proteins were formed by photolithography method. Methods of activation of carboxyl groups on brush polymers attached to the surface of polyethylene terephthalate were tested. Immobilization of model protein streptavidin labeled with fluorescent dye Su3 was performed to test the method of activation of carboxyl groups. Results and Discussion: A variant of the immunofluorescence assay in a biological microarray format was tested on the model “streptavidin–biotinylated immunoglobulin.” Conclusions: Streptavidin immobilized in brush polymer cells retains functionality and spatial accessibility for binding to biotinylated immunoglobulin and subsequent manifestation by antibodies fluorescently labeled with Cy5 dye, which opens prospects for the use of biological microarrays with brush polymer cells on polyethylene terephthalate substrates for immunofluorescence analysis of various protein targets.