Study of the effect of temperature on the properties of gelatin-chitosan cryogels

Cryopolymers are a class of 3D structural polymers, which are widely used in tissue engineering. Using cryopolymerization technology, physical cross-linked macroporous cryogels based on gelatin and chitosan were synthesized at –12 ºC, –30 ºC and –70 ºC for application as carriers for cell cultures. The presence of functional groups was investigated by IR spectroscopy. The effect of temperature on physicochemical properties such as pore volume, density, gel fraction and biodegradation of cryogels was studied. The results obtained showed that the pore volume (up to 87.6 %) and the gel fraction (up to 80 %) increased, and the density (0.078 %) and pore sizes of cryogels decreased as the temperature decreased from –12 ºC to –70 ºC. The study of biodegradation showed that, polymers had a more degradable property in relation to saline solution with an increase in the cryopolymerization temperature. The results of electron microscopy showed the porous morphology of the surfaces of the synthesized cryogels. The average pore size varied from 150 to 300 μm. The toxicity test showed that aqueous extracts from cryogels did not have a highly toxic effect on MSCs in the adipose rats tissue, since the cell viability was 55–75 %