Affiliations: Institute of Multiphase Processes, Leibniz Universität Hannover, Hannover, Germany | Clinic for Horses – Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Hannover, Germany
Note:  Corresponding author: Willem F. Wolkers, Institute of Multiphase Processes, Leibniz Universität Hannover, Callinstrasse 36, 30167 Hannover, Germany. Tel.: +49 511 762 19353; Fax: +49 511 762 19389; E-mail: [email protected]
Abstract: Cryopreservation of cells requires addition of cryoprotective agents as well as controlled freezing and thawing rates to minimize damage resulting from osmotic dehydration and intracellular ice formation. Typically, there is an optimal cooling rate for maximum survival after freezing and thawing. This cooling rate, however, can vary greatly depending upon intrinsic cellular properties such as membrane composition, osmotic properties, and subzero membrane phase and permeability behavior. In this review, we describe the application of Fourier transform infrared (FTIR) spectroscopy to study membrane phase behavior during freezing of cells. It is shown how membrane phase behavior can be used to derive the membrane permeability to water at subzero temperatures and the activation energy for water transport. In addition it is shown how subzero membrane hydraulic permeability parameters can be used to simulate the cellular dehydration response at different cooling rates to predict the optimal cooling rate. FTIR studies may thus aid in rationally designing cryopreservation protocols for cells.