Effects of Au nanoring and photosensitizer exocytosis from cancer cells on their damage efficiency through photodynamic and photothermal processes (Conference Presentation)

Abstract

Photosensitizer can be taken up directly by cells or through the linkage with gold nanoparticles (NPs). When gold NPs linked with a photosensitizer are taken up by cells, both photodynamic (PDT) and photothermal effects for damaging cells can be generated under the illumination of a light source of an appropriate wavelength. The gold NPs and photosensitizer can escape from cells through an exocytosis process such that the efficiency of cell damage may decay with time. In this study, we investigate the dependencies of cell damage efficiency, gold nanoring (NRI) and photosensitizer amounts stayed in cells on the delay time. In particular, we differentiate the two possible escape pathways of the photosensitizer, AlPcS, i.e., AlPcS escape alone after its linkage with Au NRI is broken and AlPcS escape together with the linked Au NRI. Also, we intend to understand the dependence of the aforementioned AlPcS escape pathway on the location of Au NRIs inside a cell after they are taken up. It is found that generally, the PDT-induced cell damage efficiency decays more slowly when AlPcS is taken up together with linked Au NRI, compared with the case that AlPcS is taken up alone by cells. This trend indicates that the photosensitizer is more stable when it is linked with an Au NP. This result is confirmed by the observations of Au NRI and photosensitizer escapes through mass spectrometry, flow cytometry, and confocal fluorescent microscopy.