Introduction—Fluorescence in Organic Nanoparticles

Abstract

Fluorescent organic nanoparticles (FONs) represent a very exciting class of materials in the nanoregime that are bestowed with diverse analytical and biomedical applications. Several FONs have been reported as attractive agents for cell imaging applications, and over the last few decades, several bioprobes, e.g. organic dyes, fluorescent proteins and fluorescent inorganic/organic nanoparticles, have been reported for biomedical applications. FONs are thought as more promising agents for biomedical applications owing to their possibility for diverse designs and biodegradability properties. FONs are generally composed of small organic molecules with emissive properties comparable to those of semi-conjugated polymer dots. Basically, FONs contain a high number of photo-active self-assembled units. Besides, there are no stabilizing surfactants or doping matrices within the structures of FONs, which helps them to avoid the undesirable interventions of non-active matter with living organisms. These nanoparticles show intense brightness upon one- or two-photon excitation, which helps in achieving reduced excitation fluence and tissue auto-fluorescence. This chapter highlights the usefulness of the fluorescence phenomena in the diverse classes of FONs. Besides, the increasing interest in the research on FONs as analytical and biomedical agents has been described in this chapter.