Accompanying photocytotoxic activity of gold nanoechinus and zinc phthalocyanine on cancerous cell lines.

Background: Near-infrared triggered photodynamic therapy (NIR-PDT) has been introduced as a relatively deep tumor treatment modality. The gold Nanoechinus (Au NE) is a rare type of nanostructures that act as a transducer to change NIR wavelength to ultraviolet (UV) and visible lights. During the photodynamic process, Au nanoechinus (Au NE) converts the irradiation of 980 nm to 674 nm which is absorbed by Zn(II) Phthalocyanine tetrasulfonic acid (ZnPcS). In this study the cooperation effect of Au NE and ZnPcS in PDT on MCF7 and Hela cells was investigated.

Methods: Cytotoxicity and phototoxicity of the composition having different concentrations of Au NE and ZnPcS upon irradiation of 980 nm NIR light were evaluated against MCF7 and Hela cells after two different incubation times and irradiating with two different power densities of laser.

Results: Among different experimental groups, in MCF7 cells, which were incubated for 48 h with 50 μg/mL Au NE+2μM ZnPcS and were treated by 980 nm laser with a power density of 200 mW cm for 15 and 30 min, 48 and 38% cell viability were recorded. No appreciable result was observed due to PDT of Hela cells.

Conclusions: Comparing to other PDT modalities against MCF7 cells, NIR-PDT procedure suggested in this study with the synergistic effect of Au NE and ZnPcS could be a secure promising modality in the treatment of deep-seated tumors. Carefully increasing the power density and ambient temperature, to the extent of skin tolerance threshold value, seems to be efficient in the treatment of Hela cells.