In order for researchers to successfully cryopreserve materials, chemicals known as cryoprotectants are used to help support the freezing process. Many of these cryoprotectant agents have several limitations, such as cytotoxicity.
Scientists at the Japan Advanced Institute of Science and Technology (JAIST) and Japan's RIKEN have experimented on polyampholytes. They have identified one polyampholyte named carboxylated ε-poly-lysine (COOH-PLL) as a promising cryoprotectant that does not have toxic effects on cells.
Professor Kazuaki Matsumura and Asst. Prof. Robin Rajan of JAIST and Dr. Fumiaki Hayashi and Dr. Toshio Nagashima of RIKEN--conducted another study in which they used a method called solid-state nuclear magnetic resonance (NMR) spectroscopy to characterize what happens to water molecules, sodium and chloride ions, and a form of COOH-PLL called PLL-(0.65) when they are mixed and frozen to temperatures used in cryopreservation. Their research is published in the journal, Communications Materials.
"Based on our now-improved understanding of mechanisms of polymeric cryoprotective agents," stated Prof. Matsumura, "we expect to develop new cryopreservation technologies for large tissue volumes and organs, which will permit the industrial-scale implementation of regenerative medicine via the establishment of banks of engineered tissues."
Image credit: Kazuaki Matsumura from the JAIST