Study of light emitting nanoparticles (upconverting nanophores) for biomedical and biotechnological applications

Abstract

Among the several interdisciplinary research areas emerging with nanotechnology special attention has been given to bionanophotonics, a combination of nanophotonics (the study of optical interactions in the nanoscale) with biomedical sciences and biotechnology. The many possibilities of applications in this field are based, for instance, on the use of light emitting nanoparticles in biosensing, optical diagnostics and photodynamic therapies. The different kinds of nanoparticles can be tailored to emit at specific wavelengths in the visible to infrared spectral range, convert near-infrared light to visible, as well as be functionalized to disperse in biological media and be conjugated to various types of biomolecules. In this project the study of rare-earth doped upconverting luminescent nanoparticles (UCNPs) with applications as theranostic agents, in bioimaging and in photodynamic therapy of cancer and photodynamic inactivation of bacteria is proposed. The study will be focused on the optimization of the nanoparticles luminescent and singlet oxygen quantum yields, as well as on the combination of UCNPs with additional photosensitizers. The evaluation of their cytotoxicity and on the efficacy for specific binding towards biological targets will also be carried out. In order to do so, structural, spectroscopic and optical characterizations will be used as tools to improve their synthesis and processing, aiming to obtain efficient nanoparticles to be further tested and used in cytological and histological testing.