Antibody-Conjugated Rubpy Dye-Doped Silica Nanoparticles as Signal Amplification for Microscopic Detection ofVibrio choleraeO1

Abstract

This study demonstrated the potential application of antibody-conjugated Rubpy dye-doped silica nanoparticles for immunofluorescence microscopic detection ofVibrio choleraeO1. The particle synthesis of 20X of the original ratio was accomplished yielding spherical nanoparticles with an average size of45±3 nm. The nanoparticles were carboxyl functionalized and then conjugated with either monoclonal antibody or polyclonal antibody againstV. choleraeO1. The antibody-conjugated nanoparticles were tested with two target bacteria and three challenge strains. The result showed that monoclonal antibody-conjugated Rubpy dye-doped silica nanoparticles could be effectively used as signal amplification to detectV. choleraeO1 under a fluorescence microscope. Their extremely strong fluorescence signal also enables the detection of a single cell bacterium.