Nanosurgery of cells and chromosomes using near-infrared twelve-femtosecond laser pulses

Saarland University, Department of Biophotonics and Laser Technology, Campus A5 1, 66123 Saarbruecken, Germany.
Journal of Biomedical Optics (Impact Factor: 2.86). 10/2012; 17(10):101502-1. DOI: 10.1117/1.JBO.17.10.101502
Source: PubMed


Laser-assisted surgery based on multiphoton absorption of near-infrared laser light has great potential for high precision surgery at various depths within the cells and tissues. Clinical applications include refractive surgery (fs-LASIK). The non-contact laser method also supports contamination-free cell nanosurgery. In this paper we describe usage of an ultrashort femtosecond laser scanning microscope for sub-100 nm surgery of human cells and metaphase chromosomes. A mode-locked 85 MHz Ti:Sapphire laser with an M-shaped ultrabroad band spectrum (maxima: 770  nm/830  nm) and an in situ pulse duration at the target ranging from 12 fs up to 3 ps was employed. The effects of laser nanoprocessing in cells and chromosomes have been quantified by atomic force microscopy. These studies demonstrate the potential of extreme ultrashort femtosecond laser pulses at low mean milliwatt powers for sub-100 nm surgery of cells and cellular organelles.

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    Proceedings of SPIE - The International Society for Optical Engineering 02/2012; 8249:14-. DOI:10.1117/12.908284 · 0.20 Impact Factor
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