FRET-mediated quenching of BODIPY fluorescent nanoparticles by methylene blue and its application to bacterial imaging

摘要

High resolution and a good signal to noise ratio are a requirement in cell imaging. However, after labelling with fluorescent entities, and after several washing steps, there is often an unwanted fluorescent background that reduces the images resolu- tion. For this purpose, we developed an approach to remove the signal from extra-cellular fluorescent nanoparticles (FNPs) during bacteria imaging, without the need for any washing steps. Our idea is to use methylene blue to quench > 90% of the emission of BODIPY-based fluorescent polymer nanoparticle by a FRET process. This “Hide-and-Seek Game” approach offers a novel strategy to apply fluorescence quenching in bioimaging to improve image accuracy.