Shell cross-linked nanoparticle eased on poly(ε-caprolactone)- poly(ethylene glycol) for photosensitizer delivery

Polymeric micelles as drug carriers attract highly concern recent years for their ability to incorporate hydrophobic drugs. Photodynamic therapy (PDT) is a promising new cancer treatment that involves the combination of visible light and a photosensitizer. In this study, protoporphyrin IX (PpIX) was encapsulated into shell crosslinked nanoparticles (SCKs) for photosensitizer delivery to reduce the side effects of PDT. The particle size of the SCKs without drug was about 140 nm, and the size of the SCKs with PpIX were about 240 nm. The cytotoxicity reveals that SCKs/PpIX have some toxicity to normal cell line. As shown in the results of fluorescence microscopy and flow cytometry, the uptake of SCKs with PpIX reach the maximum at the incubation time of 12-24 hours. The PDT effects of SCKs/PpIX show no significant differences with free PpIX. In summary, in vitro characterization and in vitro PDT effect of SCKs encapsulated with PpIX were studies. These results may lead to more successful development on the application of SCKs for photodynamic therapy.