Opto-electrochemical functionality of Ru(II)-reinforced graphene oxide nanosheets for immunosensing of dengue virus non-structural 1 protein

Publication date: Available online 14 November 2019Source: Biosensors and BioelectronicsAuthor(s): Pandiyaraj Kanagavalli, Murugan VeerapandianAbstractTransforming the structural and functional properties of carbon nanostructures are highly beneficial for healthcare diagnostics. This research demonstrates the functionalization of opto-electrochemically active ruthenium bipyridine complex (Ru(II)) on the surface of graphene oxide (GO), enabling a dual-functional immunoprobe for the detection of non-structural 1 (NS1) protein, a dengue biomarker. Structural investigations reveals that Ru(II) has intermolecular bonding with functional groups of GO. Ultraviolet photoelectron spectral readouts display the changes in the work function and ionization energy of GO, supporting the functionalization of Ru(II). Bio-affinity layers of protein-G (Pro-G) at GO-Ru(II) electrode interface promotes the localization of monoclonal antibodies (mAb) selective for binding the epitopes of NS1 antigen. The chronoamperometric and fluorescence quenching-based immunoassays showed a linear response with a lowest detection limit of 0.38 and 0.48 ng/mL, respectively. Under optimal condition, the developed immunosensor studied to have retained stability/sensitivity toward NS1 without impact from interferents. The dual functional immuno-bioprobe translated from GO-Ru(II) conjugated nanostructures offers new insights for further studies in on-site diagnosis.
Source: Biosensors and Bioelectronics - Category: Biotechnology Source Type: research