Micro-manipulation system with a two-fingered micro-hand and its potential application in bioscience.

A micro-manipulation system using a two-fingered micro-hand, an auto-focusing optical microscope, and user interfaces was developed. This micro-hand has 6 degrees of freedom (DOF): 3 DOF for each of the two fingers. These fingers work just like the thumb and forefinger. Thus, this hand can grasp, move, rotate, and release micro-objects, such as biological cells. A human operator can operate this hand using a joystick or a keyboard, while seeing the microscope image displayed on a monitor. The present paper describes two applications of this system to the field of bioscience. The first application involves extraction of cytoplasm from a cell using two, two-fingered micro-hands. One hand holds the cell firmly, while the other hand makes a hole in the cell and tears it. Then, the hand holding the cell squeezes the cytoplasm from the cell. The second application involves measurement of the mechanical properties of living cells using the micro-finger and a micro-force sensor based on the Atomic Force Microscope (AFM) principle. The AFM cantilever is placed within the microscopic field. The micro-finger holds a cell and presses it against the cantilever tip. By measuring the pressing force and the deformation of the cell, the cell's force-deformation curve is obtained.