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arXiv · 2401.06906

Femtosecond laser-assisted selective holding with ultra-low power for direct manipulation of biological specimens

Krishangi Krishna·Joshua A. Burrow·Zhaowei Jiang·Wenyu Liu·Anita Shukla·Kimani C. Toussaint Jr
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Abstract

Traditional optical tweezers techniques often rely on high-power continuous wave (CW) lasers, which can introduce unwanted thermal effects and photodamage to delicate samples. To overcome these limitations, we demonstrate femtosecond laser assisted selective holding with ultra-low power (FLASH-UP). We find that the FLASH-UP exhibits a five times greater trap stiffness than CW-OT, and can trap at lower intensities. Furthermore, we demonstrate OT of different pathogenic bacteria species and find that FLASH-UP does not impact cell motility. These results pave the way for applications in sorting, bio-sensing, in vivo cell manipulation and single cell analysis.

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Krishangi Krishna, Joshua A. Burrow, Zhaowei Jiang, Wenyu Liu, Anita Shukla, Kimani C. Toussaint Jr. 2024-01-12. Femtosecond laser-assisted selective holding with ultra-low power for direct manipulation of biological specimens. https://doi.org/10.1117/1.jbo.29.8.086501

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