Embryo transfer method and apparatus

Claim 3

The method of claim 1 wherein said diluent is sucrose.

Claim 4

The method of claim 1 wherein said cryoprotective agent is selected from the group consisting of dimethyl sulfoxide, glycerol, and low molecular weight glycols.

Claim 5

The method of claim 2 wherein said cryoprotective agent is glycerol.

Claim 6

The method of claim 1 wherein said thawing of said volume is allowed to occur in an uncontrolled manner by allowing same to reach ambient temperature.

Claim 7

The method of claim 1 wherein said volumetric amount of diluent solution is at least about six times as great as the volume of said volume of cryoprotective agent.

Claim 8

The method of claim 1 wherein said transfer of said dilution mixture is performed surgically.

Claim 9

The method of claim 1 wherein said transfer of said dilution mixture is performed nonsurgically.

Claim 10

The method of claim 1 wherein said cryoprotective agent is glycerol in a PBS solution in a concentration of from about 1.0 M to about 2.0 M and wherein said diluent solution is sucrose in a PBS solution in a concentration of from about 0.5 M to about 1.0 M.

Claim 11

In a method for thawing and transferring embryos frozen in a volume of a cryoprotective solution containing a cryoprotective agent to a suitable recipient at a synchronized time wherein the cryoprotective solution is diluted in a onestep process, the improvement comprising: (a) preparing a premeasured diluent solution for combining with said volume to form a dilution mixture, said diluent solution having a volume effective, when combined with the volume of cryoprotective solution, to reduce the concentration of the cryoprotective agent in solution to a nonharmful level, said diluent solution having a concentration of a nontoxic, nonpermeating compound sufficient to be substantially isosmolal with the cryoprotective solution; (b) thawing the volume of cryoprotective agent; (c) combining the thawed volume with the premeasured diluent solution to form said dilution mixture; (d) allowing sufficient time for dilution to occur; and (e) delivering said dilution mixture to the recipient where washing of said dilution mixture from said embryo occurs.

Claim 12

In a method for thawing and transferring embryos frozen in a volume of a cryoprotective solution containing a cryoprotective agent to a suitable recipient at a synchronized time wherein the cryoprotective solution is diluted in a onestep process, the improvement comprising: (a) preparing a premeasured diluent solution for combining with said volume to form a dilution mixture, said diluent solution having a volume effective, when combined with the volume of cryoprotective solution, to reduce the concentration of the cryoprotective agent in solution to a nonharmful level, said diluent solution having a concentration of a nontoxic, nonpermeating compound sufficient to be substantially isosmolal with the cryoprotective solution; (b) thawing the volume of cryoprotective agent; (c) combining the thawed volume with the premeasured diluent solution to form said dilution mixture; (d) allowing sufficient time for dilution to occur; and (e) delivering said dilution mixture to the recipient where washing of said dilution mixture from said embryo occurs.

Claim 13

The improved method of claim 10 wherein said diluent is sucrose.

Claim 14

The improved method of claim 11 wherein said cryoprotective agent is glycerol.

Claim 15

The method of claim 12 wherein the volumetric ratio of cryoprotective solution to diluent solution is in the range of from approximately 1:6 to approximately 1:10.

Claim 16

The method of claim 10 and further comprising imparting gentle mixing action to said dilution mixture during step (d) thereof.

Claim 19

The method of claim 15 wherein said container comprises a tubular structure and means for separating said tubular structure into a first chamber for containing said volume and embryo and a second chamber for containing said effective amount of diluent solution.

Claim 20

The method of claim 16 wherein said separation means comprises an air bubble.

Claim 21

The method of claim 15 wherein combination of said diluent solution and volume of cryoprotective agent is achieved by imparting centrifugal force to said container.

Claim 22

The method of claim 15 wherein said diluent solution is a solution of sucrose in a phosphate-buffered saline solution.

Claim 23

The method of claim 15 wherein said volume of cryoprotective agent comprises a phosphate-buffered solution of glycerol.

Claim 24

The method of claim 15 wherein the container is thawed at the situs of the recipient animal.

Claim 25

The method of claim 21 wherein said transferring of the contents of said container to the recepient is performed nonsurgically.

Claim 26

The method of claim 22 wherein said nonsurgical transfer is effected with an artificial insemination gun.