Cellular Reactions of Organic Nanoparticles During PDT

Organic crystalline nanoparticles (NPs) are not fluorescent due to the crystalline structure of the flat molecules organized in layers. For Aluminum Phthalocyanine (AlPc)- derived NPs, preferential uptake and dissolution by macrophages were demonstrated recently. Therefore, inflamed tissue or cancer tissue with accumulated macrophages (M1; M2 polarization state) may exhibit specific fluorescence in contrast to normal tissue, which does not fluoresce. The present study addresses the photobiological effects of NP generated from the clinically utilized photosensitizer Temoporfin (mTHPC).