Investigation of photodamage by femtosecond laser to cells via gold nanorods

Abstract

Usually, only focused femtosecond (fs) lasers at near-infrared (NIR) range can induce photodamage to transparent cells, making it di±cult to treat large amount of cells by such optical methods for photostimulation. In this study, we clarify the mechanism of photodamage to cells that are co-cultured with gold nanorods (GNRs) by fs laser. The pulse duration and repetition rate of the fs laser play a key role in cell damage suggesting that the heat accumulation contributes to the major part for the cell damage rather than the high peak power which mainly determines the e±ciency of multiphoton excitation. We further show that cellular Ca 2þ can also be released in this scheme, but the process is more sensitive to peak power. Our results can provide a large-scale GNR-mediated photostimulation for cell signaling modulation.

Trans-scale live imaging of an E5.5 mouse embryo using incubator-type dual-axes light-sheet microscopy

“…We expected a temperature increase inside an EB by strong laser irradiation, as previously reported, 30 because the EB growth tested in this study was also affected by the temporal temperature increase in the culture medium (Supplementary Fig. 8).…”