Rapid electromagnetic warming of cells and tissues.
We describe a system for thawing frozen cell suspensions and tissues by electromagnetic absorption. A 25-ml sample is heated in a cylindrical resonant cavity, which is excited in three modes all close to 434 MHz. Maximum warming rates are over 10 degrees C/s (600 C/min), and a frozen sample may be brought from -65 degrees C to room temperature in < 30 s, with final spatial differences of < 20 degrees C. Samples may be frozen externally, or cooled within the cavity at typically 1 degree C/min. We have also used the resonant cavity to measure the permittivity and conductivity of the sample at temperatures from -83 degrees C to +8 degrees C. By measuring the heat capacity of the sample, we have calculated the power deposited in it as a function of its temperature. The system is currently being used to investigate the effect of warming rate on cell survival.
Robinson
M P
MP
Department of Biology, University of York, Heslington, U.K. mpr@ohm.york.ac.uk
Pegg
D E
DE
D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods; D002460:Cell Line; D015925:Cryopreservation / Q000295:instrumentation* / Q000379:methods*; D006358:Hot Temperature / Q000627:therapeutic use*; D009926:Organ Preservation / Q000379:methods*; D011827:Radiation; D013997:Time Factors