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Optical Tweezers Allow DNA to be Inserted Gently into Individual Living Cells – This technique minimizes damages to cells and enables controlling the time when, location to which, and how much DNA is inserted selectively.
□ A team of South Korean scientists have developed the most precise method to insert DNA into cells. This method allows researchers to puncture the membranes of individual cells with lasers and then place a piece of DNA through the cells using *optical tweezers. This can minimize damages to cells and is expected to be useful for gene therapy and biotechnology researches.
<* Optical tweezers tweak a laser beam whose electromagnetic field can grab hold of and transport a micro-sized particle without actually touching the particle.>
o This research is conducted by Lee Yong Gu, an associate professor in the School of Mechatronics at the Gwangju Institute of Science and Technology (GIST, President Young Joon Kim), Muhammad Waleed (lead author), and other researchers and is sponsored by the Mid-Career Researcher Program (Core Research) which the National Research Foundation of Korea (President: Lee, Seung Jong) and the Ministry of Science, ICE & future Planning (Minister: Choi, Mun Kee) lead. This research was published in the Optical Society’s (OSA) online journal Biomedical Optics Express, Vol. 4, Issue 9 (title: Single-cell optoporation and transfection using femtosecond laser and optical tweezers).
□ Common methods to insert DNA are so-call “gene-gun” to fire nano-sized particles coated with strands of DNA at large population of cells like shooting a gun or giving electric shock. Such methods cannot guarantee whether any individual cell will incorporate the desired genes, and large numbers of cells may be damaged or destroyed in the process.
□ Researchers precisely poke holes on the surface of a single cell with a high-powered *femtosecond laser and then pushed the particle coated with genes through the holes with the optical tweezers.
<* Femtosecond laser creates an ultra-short laser pulse which blinks at an interval of 10-15 seconds and can make tiny pores on the membranes of individual cells without inflicting heat damage.>
□ A femtosecond laser creates a “tunnel” through which a plasmid-coated particle can pass. After the particle is dropped into the pores of cells, the tunnel is closed as the cells are healed.