Dielectric properties of supercooled cryoprotectant agents.

The dielectric properties of glycerol, propylene glycol, ethylene glycol and dimethyl sulphoxide have been measured in various aqueous concentrations generally sufficient to allow supercooling rather than freezing. The temperature range investigated is from -80 degrees C to +20 degrees C and the frequency range is 100 MHz to 2 GHz. The aim is to find the materials and conditions most favorable for very rapid re-warming of perfused biological tissue by electromagnetic fields, avoiding thermal runaway in the bulk and local non-uniformity of temperature. Frequencies below 500 MHz are generally indicated.