Application of GBP-fusion protein in SPR and electrochemical detection of biomarkers

Abstract

Protein-protein interaction in cells plays key roles in many essential biological processes that are involved in gene expression, receptor-ligand interaction, enzyme assembly and the regulation of metabolic reaction. Identification of these interactions and characterization of their physiological significance constitute one of the main goals of current biological research. Towards this goal, several technologies including two-hybrid system, protein microarrays or chips have been developed and used for studying interactions. In this study, we have investigated the application of genetically engineered GBP-fusion protein to immobilize protein onto the solid chip and exploited its potential utility for biosensor application of viral diseases. In this approach, protein attachment is achieved through its specific affinity between GBP and gold surface, and no complicated chemical modification of solid supports is involved, thus making the molecular-level processing for nanostructural control at the lowest dimensional scale prospective. Two models were tested: SARS diagnosis via antibody detection and HBV infection diagnosis via antigen detection, both of which involves GBP-fusion protein as immobilizing avenue and AFM imaging, SPR and electrochemical assay were carried out to evaluate its characteristics.