Functionalized silica-based nanoparticles for photodynamic therapy.

Aim: The strategy developed aims to favor the vascular effect of photodynamic therapy by targeting tumor-associated vascularization using peptide-functionalized nanoparticles. We previously described the conjugation of a photosensitizer to a peptide targeting neuropilin-1 overexpressed in tumor angiogenic vessels.
Materials & Methods: In this study, we have designed and photophysically characterized a multifunctional nanoparticle consisting of a surface-localized tumor vasculature targeting peptides and encapsulated photodynamic therapy and imaging agents.
Results & Conclusion: The elaboration of these multifunctional silica-based nanoparticles is reported. Nanoparticles functionalized with approximately 4.2 peptides bound to recombinant neuropilin-1 protein. Nanoparticles conferred photosensitivity to cells overexpressing neuropilin-1, providing evidence that the chlorin grafted within the nanoparticle matrix can be photoactivated to yield photocytotoxic effects in vitro.