US 6,982,172 B2
Oocyte vitrification technique
Xiangzhong Yang, Storrs, Conn. (US); and Andras Dinnyes, Budapest (Hungary)
Assigned to University of Connecticut, Farmington, Conn. (US)
Filed on Jan. 04, 2001, as Appl. No. 9/755,205.
Claims priority of provisional application 60/215433, filed on Jun. 30, 2000.
Claims priority of provisional application 60/174383, filed on Jan. 04, 2000.
Claims priority of provisional application 60/174424, filed on Jan. 04, 2000.
Prior Publication US 2002/0009704 A1, Jan. 24, 2002
Int. Cl. A01N 1/02 (2006.01); C12N 5/06 (2006.01)
U.S. Cl. 435—374 17 Claims
 
1. A method for cryopreservation of bovine oocyte morphology and viability, comprising the steps:
(a) suspending bovine oocytes in a medium comprising about 4% ethylene glycol and about 20% bovine serum for about 15 min at a temperature at or near physiological temperatures;
(b) rinsing the oocytes for about 30 seconds in a solution comprising about 35% ethylene glycol, 0.4 M trehalose, 20% bovine serum and 5% polyvinylpyrrolidone;
(c) vitrifying the oocytes in step (b) by quickly dropping microdroplets of the solution comprising the oocytes onto a solid surface that has a temperature between −150° C. and −180° C.; and
(d) collecting frozen microdroplets that contain vitrified oocytes that maintain morphology and viability after thawing.