E.-J. Jo, D. Hong, M.-G. Kim
Gwangju Institute of Science and Technology (GIST),
Keywords: biosensor, immunosensor, photothermal effect, stimuli-responsive materials, diagnosis
Summary:In this study, we report a bioluminescence-based immunosensor for target protein detection using thermo-triggered ATP release from polymeric micelles-coated nanoparticles by photothermal heating of gold nanorods (GNRs). The immunosensor is comprised target specific detection antibody-conjugated GNRs (GNRs conjugates) and silica nanoparticles conjugated with capture antibody and ATP-loaded micelles (ATP micelles-silica conjugates). When target protein was added, these conjugates allow identifying target protein by the specific recognition between GNRs conjugates and ATP micelles-silica conjugates via sandwich immunoassay. Then, the localized photothermal heating in the GNRs conjugates under NIR irradiation causes thermo-triggered ATP release of ATP micelles-silica conjugates from the targeted sandwich conjugates by target protein. Consequently, the target-mediated ATP release from the thermo-responsive polymeric micelles produces a bioluminescent signal via bioluminescent firefly luciferin/luciferase reaction. Therefore, the bioluminescent signal increased with increasing concentration of target protein without the need for multiple steps. Thus, we believe that the proposed immunosensor has a significant potential as a diagnostic tool and clinical monitoring for sensitive detection of target protein in a homogeneous manner.