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bioRxiv · 10.1101/2024.10.29.620774

Induction of cell death in U2OS human cancer cells by Ta3N5

Nozaki, T.·Watanabe, K.·Watanabe, T.·Nakamura, T.
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Abstract

Photocatalysts are widely used in modern society, with their applications extending into the field of medicine. Ultraviolet irradiation is used for photocatalysis to generate reactive oxygen species (ROS). Ta3N5 has attracted attention as a next-generation photocatalyst because it produces ROS upon exposure to visible light. Although ROS generation using visible light irradiation is useful in the field of life sciences, the toxicity of Ta3N5 remains unknown. In the present study, we evaluated the cytotoxicity of Ta3N5 using U2OS cells in terms of the intensity, irradiation time, and wavelength of light and Ta3N5 dose. We also investigated the mode and mechanism of cell death induced by Ta3N5. Cytotoxicity increased with increasing light intensity, irradiation time, and Ta3N5 dose. In contrast, high-intensity blue light irradiation induced cytotoxicity with or without Ta3N5, indicating that irradiation to green and red lights, which can selectively toxify Ta3N5-treated cells, is more useful than irradiation to blue light. Moreover, Ta3N5 induced secondary necrotic death of U2OS cells. These results suggest that Ta3N5 can be used as a photocatalyst in medical and life science fields.

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Nozaki, T., Watanabe, K., Watanabe, T., Nakamura, T.. 2024-10-30. Induction of cell death in U2OS human cancer cells by Ta3N5. https://doi.org/10.1101/2024.10.29.620774

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