X-Message-Number: 7448 From: (RL) Newsgroups: sci.cryonics Subject: freezing suggestions Date: Tue, 07 Jan 1997 11:24:14 GMT Message-ID: <> I used to do lab research on cell membranes a few years ago. One method we used was to create a surface replica of the membrane and examine it under electron microscopy. To do this, we obviously needed to work with intact, non-ruptured cells. We found that placing tissue directly in liquid nitrogen didn't work because the LN has too low a thermal density, and doesn't therefore remove the heat fast enough, allowing the water in the cells to crystalize and cause damage. Instead, we first placed the tissue in liquid freon and allowed it to cool that way. The freon is higher temperature but also much higher thermal density and cooled the tissue quickly enough to avoid crystalization. We then placed the tissue in liquid nitrogen for final cooling. My suggestion is the following procedure: 1) Replace blood with synthetics which do not crystalize as easily 2) Lower the body temperature to near freezing 3) Cut open the body and most particularly the skull, to allow maximum penetration of the coolant. At this stage organs may need to be exposed and freed from their surrounding connective tissue to allow maximum coolant contact. 4) Immerse the body in liquid freon until frozen. At this stage it may be necessary to provide tubes and channels to make sure the coolant penetrates all body cavities quickly. The lungs, in particular, and the brain may require special preparation and cooling. 5) Transfer to liquid nitrogen. Has this been tried? Any comments? RL ***************************** I DO NOT want unsolicited e-mail & I will bill you for it. By US Code Title 47, Sec. 227(a)(2)(B), a computer/modem/printer meets the definition of a telephone fax machine. By Sec.227(b)(1)(C), it is unlawful to send any unsolicited advertisements to such equipment, punishable by action to recover actual monetary loss, or $500, whichever is greater, for each violation. Pursuent to US Code, Title 47, Chapters 5, Subchapter II, Sec. 227, any and all non-solicitied commercial e-mail sent to this address is subject to a download & archival fee of $500 US. E-mailing denotes acceptance of these terms. ***************************** Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=7448