Method of freezing human blood platelets in glycerol-glucose using a statically controlled cooling rate device
US4251995A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1979 |
| Grant date | Feb 24, 1981 |
| Priority date | — |
| Expiry date | Apr 25, 1999 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M1/0277
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An inexpensive, statically controlled cooling rate device comprising a cassette of metal plates and cardboard insulation in a plastic bag was used to freeze platelets in liquid nitrogen with glycerol-glucose as cryoprotectant. Depending on the thermocouple location, the cooling rate in the freezing bag varied between 22.1.degree. and 38.6.degree. C. per minute, averaging 33.6.degree..+-.1.1.degree. C. per minute at the center. The post-thaw recovery of platelets frozen with this device and reconstituted in plasma averaged 88.6.+-.11.7 percent, compared to 86.1.+-.9.9 percent for nonfrozen but identically processed platelets. [.sup.14 C]Serotonin uptake after 0.5-hour incubation was 95.9.+-.1.9 percent for fresh platelets in platelet-rich plasma, 92.7.+-.4.4 percent for nonfrozen processed platelets, and 81.4.+-.11.8 percent for frozen platelets, increasing to 85.9.+-.7.7 percent after one-hour incubation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.