Experimental Study On The Cell Fusion Using Femtosecond Laser Cell Micromanipulation System

Cell fusion is an important technology in biotechnology and bioengineering. Traditional methods have a very low rate of cell fusion because of the larger the chemical or physical injury. Femtosecond laser can achieve a high peak power density with tiny single pulse energy. In biological applications, the advantages of higher temporal and spatial resolution are widely used in the researches, such as cell surgery, foreign DNA trasfection and so on.This dissertation concentrates on the series of experimental researches of the femtosecond laser-induced cell fusion using femtosecond laser cell micromanipulation system. In this paper, the main contents include:1. In theory, the mechanism of the interaction between the femtosecond laser and biological material has been discussed.2. The structure and the adjustment of the femtosecond laser cell micromanipulation system has been described. The functions of the optical tweezers and the femtosecond laser scalpel have been achieved. We also propose the improvement of the femtosecond laser cell micromanipulation system.3. We study on the damage threshold of phaffia rhodozyma cells and protoplasts by the femtosecond laser, in order to find the appropriate parameter of the femtosecond laser-induced cell fusion.4. The femtosecond laser-induced phaffia rhodozyma protoplast fusion has been achieved, using PEG as the means of cells congregating. The repeated experiments show the rate of cell fusion under the different input power and find the threshold of the femtosecond laser-induced cell fusion. Then we have some discussion on the mechanism of femtosecond laser-induced cell fusion.5. At last, we make some suggestions of the future work.