Room-temperature ionic liquids meet bio-membranes: the state-of-the-art

Abstract

Room-temperature ionic liquids (RTIL) are a new class of organic salts whose melting temperature falls below the conventional limit of 100 °C. Their low vapor pressure, moreover, has made these ionic compounds the solvents of choice of the so-called green chemistry. For these and other peculiar characteristics, they are increasingly used in industrial applications. However, studies of their interaction with living organisms have highlighted mild to severe health hazards. Since their cytotoxicity shows a positive correlation with their lipophilicity, several chemical–physical studies of their interactions with biomembranes have been carried out in the last few years, aiming to identify the molecular mechanisms behind their toxicity. Cation chain length and anion nature of RTILs have seemed to affect lipophilicity and, in turn, their toxicity. However, the emerging picture raises new questions, points to the need to assess toxicity on a case-by-case basis, but also suggests a potential positive role of RTILs in pharmacology, bio-medicine and bio-nanotechnology. Here, we review this new subject of research, and comment on the future and the potential importance of this emerging field of study.

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Acknowledgements

A.B. thanks Prof. Pietro Ballone for fruitful discussions, and acknowledges support from (i) The European Community under the Marie-Curie Fellowship Grants HYDRA (No. 301463) and PSI-FELLOW (No. 290605), and (ii) The Science Foundation Ireland (SFI) under the Start Investigator Research Grant 15-SIRG-3538, with additional support provided by the School of Physics, University College Dublin, Ireland, and the Laboratory for Neutron Scattering, Paul Scherrer Institute (PSI), Switzerland.

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This article is part of a Special Issue on ‘IUPAB Edinburgh Congress’ edited by Damien Hall

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Benedetto, A. Room-temperature ionic liquids meet bio-membranes: the state-of-the-art. Biophys Rev 9, 309–320 (2017). https://doi.org/10.1007/s12551-017-0279-1

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Keywords

  • Ionic liquids
  • Biomembranes
  • Phospholipid bilayers
  • Toxicity
  • Biomedicine
  • Nanotechnology