Research Highlights 07
First-Ever Successful Cell Culture at an Ionic Liquid Interface
2025.01.22
Ionic liquids, composed solely of cations and anions, exhibit unique properties distinct from molecular liquids. Takeshi Ueki has successfully cultured cells at ionic liquid interfaces and is now working to further optimize the efficiency of this technique.
Takeshi Ueki
Senior Researcher, Mechanobiology Group
Unique liquids that barely evaporate or boil
Liquids like water and alcohol consist of molecules, while ionic liquids are composed entirely of cations and anions. Despite being in a liquid state, they have extremely low volatility and do not evaporate or boil under normal conditions. Additionally, their properties—such as hydrophilicity, hydrophobicity, and polarity—can be precisely tuned by modifying their chemical structures. By exploiting these unique properties, Ueki has been developing innovative methods for culturing cells at ionic liquid interfaces.
The standard method for cell culture today involves growing cells at the interface between a plastic dish and an aqueous protein-containing medium, a solid-liquid interface. In contrast, Ueki is exploring a novel approach to culture cells at liquid-liquid interfaces formed between an aqueous protein solution and a hydrophobic ionic liquid.
“The use of plastic plates confines cell cultures to the dish surface, however, a liquid-liquid interface allows for a significant increase in the available culture area by dispersing droplets of the medium throughout the solution. Furthermore, because ionic liquids neither evaporate nor boil, they can be reused after heating, drying, and sterilization, offering a notable advantage.” Ueki explained.
The challenge, however, was the cytotoxicity of hydrophobic ionic liquids to cells. To overcome this, Ueki developed a cellular toxicity evaluation method to screen for non-cytotoxic ionic liquids and he was able to successfully culture human mesenchymal stem cells at ionic liquid interfaces for the first time globally.
