The development of methods for cryopreservation of biomaterial advances the possibilities of modern biology (contributes to the preservation of endangered species, the creation of cryobanks of microorganisms) and medicine (preservation and transplantation of organs, creation of cryobanks of stem cells and blood cells). Cryoprotectors are used to protect cells from damage. Usually the efficiency of a cryoprotectant is assessed by changes in vital cell parameters after freezing. So, the success of cryopreservation of spermatozoa is estimated by their mobility, cell morphology, membrane integrity and DNA fragmentation. For individual components of cryoprotectants, physical parameters such as glass transition temperature, viscosity, toxicity and the minimum concentration necessary for vitrification are also known. However, it is impossible to find any physicochemical characteristics of cryopreservation media consisting of combinations of penetrating and non-penetrating components into the cell. An adaptation of the adiabatic calorimetry method for the study of liquid media is proposed. The dependence of heat capacity on temperature was measured and the main calorimetric characteristics (changes in entropy ΔS and enthalpy ΔH) for a glycerol-containing cryoprotectant that are actively used for the freezing and storage of semen were determined.
cryoprotectant, glycerin, adiabatic calorimetry, ART
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