Opto-injection into Single Living Cells by Femtosecond Nir Laser: a Novel Technique of Delivering Materials into Liveing Cells

This dissertation presents a novel technique of delivering membrane impermeable molecules into single living cells with the assistance of femtosecond (fs) near-infrared (NIR) laser pulses. This technique promises several major advantages, namely, very high transfection efficiency, high cell survival rate (¿100%) and fully preserved cell viabilities. In this work, the system for fs NIR opto-injection was designed and built. Successful fs NIR opto-injection has been performed on several cell systems including single mammalian cells, marine animal eggs, and human cancer cells cultured in a tissue-like environment. The connections between laser parameters and cell responses were explored. Dye uptake rate of the target cells was observed to depend on incident laser intensity. Pore size was found dependent on incident laser intensity. The conclusion was made that laser-induced breakdown and plasma-induced ablation in cell membrane are the physical principles that govern the process of fs NIR opto-injection.