A method of cryopreservation of biological material includes the steps of providing an apparatus including a vessel having a reservoir wherein the vessel has a channel formed in a portion of the reservoir, the channel including an intermediate restriction dimensioned to resist passage of the biological material but allow passage of liquid treatment solutions, and the channel including sub-reservoirs at either end of the restriction; introducing the biological material into a reservoir region of the apparatus for capture in a channel region of the vessel; irrigating and draining the biological material with a series of vitrification solutions introduced into a first of the sub-reservoirs and removed from a second of the sub-reservoirs; final draining the irrigation solutions from the vessel; and vitrifying the vessel and captive biological material.