Development of Automated Nuclear Transplantation System

In nuclear transplantation, especially in enucleation, rotatingthe oocyteto a certain position has been an important work. Therefore, we developed an oocyte rotation systemby using electrostatic force, which is known to be excellent in handling minute objects. This system has become the basic technology for the automated nuclear transplantation system. Mouse oocyles were rotatedat a speed of about 60 deg/s by electrostaticphenomena (i.e. electrorotationand dielectrophoresis), and the direction of rotationcould be reversed. In order to confirm the electrostaticeffect on the fertilization and developmental ability of oocytes, we performed IVF and nuclear transplantation with rotated oocytes. The result was that the fertilization and developmental ability of the rotated oocyteswas the same as that of the control, proving that rotationby electrostaticforce does not influence the fertilization and development ability of oocytes.