Table 2.

Warming rates attained using different thawing devices^a

Rewarming method	Mean warming rate, ° C/min ± SEM
	−150 to −80° C	−80 to −20° C	−20 to 0° C
37° C stirred water bath	348.2±17.4	117.5±17.4	14.3±1.1
37° C incubator (+ CoolRack™ CFT30)	168.0±6.7	55.9±0.4	7.2±0.2
Biocision ThawStar™ (from −193° C)	164.7±3.4	46.7±0.9	15.2±0.7
Biocision ThawStar™ (from −79° C)		41.3±1.1	14.1±0.6
37° C bead bath	118.0±1.5	35.4±0.3	4.3±0.2
20° C bench (static air)	59.5±2.6	18.6±0.3	2.2±0.1
37° C incubator (circulating air)	54.1±2.6	23.2±0.5	3.9±0.1

^aSpecially adapted cryovials housing thin wire thermocouples and containing 1 mL of CPA were frozen and stored in a charged dry shipper at −193° C for 24 h before thawing under one of the above thawing conditions. Temperature was recorded every 500 ms. Mean warming rate (WR) was based on 4 technical replicates per experiment and a minimum of three experiments per device. Samples thawed in the Biocision ThawSTAR™ were thawed from both dry shipper and dry ice temperatures according to the manufacturer's instructions. The Biocision CoolRack™ was prewarmed overnight before use and its temperature and that of the 37°C incubator measured between cryovial warming runs to ensure that temperature remained constant. Note similarity in WR for bench and incubator thawed samples which is related to the poor heat transfer properties of air. More rapid conductive rewarming in the Biocision CoolRack™, compared to passive warming in the incubator, is the result of the improved heat transfer properties of this device.