The purpose of this study is to clarify whether microencapsulated cells have an advantage over suspended cells in cryopreservation. Rat pheochromocytoma (CP 12) cells were selected for test biological cell and microencapusulated in alginate-polylysine-alginate membranes. Microencapsulated PC 12 cells were frozen with differential scanning calorymetry (DSC) at a cooling rate of 0.5 to 10°C/min. Their latent heat were measured in freezing process over the temperature range 4 to-80°C. The post-thaw viability was evaluated with dopamine release and trypan blue exclusion assay. As a result, latent heat of encapsulated cells were lower than that of suspended cells at a cooling rate of 0.5 and l°C/min. This is because extra-capusle was frozen and intra-capsule unfrozen, as ice crystals forms in extra-capsule space. The post-thaw vability of microencapsulated PC 12 cells was improved at 0.5 and 1°C/min compared with that of suspended cells. Therefore, in microencapsulated PC 12 cells, acievement of intra-capsules unfrozen condition during freezing leads to reducing the solution effect and improving the post-thaw viability.
|ジャーナル||Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B|
|出版ステータス||Published - 2001 2|
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