Biophysical Reviews

, Volume 10, Issue 3, pp 927–929 | Cite as

Ionic liquid-based transmission electron microscopy for herpes simplex virus type 1

  • Tetsuya Tsuda
  • Koshi Kawakami
  • Eiko Mochizuki
  • Susumu Kuwabata
Letter to the Editor


Ionic liquid (IL), which is often called room-temperature ionic liquid, ambient-temperature ionic liquid, and ambient-temperature molten salts, is a liquid salt composed entirely of cations and anions, and it melts below 298 K without any solvents. It is expected to be an innovative liquid material and a functional solvent due to its interesting physicochemical properties such as flame resistance, relatively high conductivity, negligible vapor pressure, and antistatic properties. Various next-generation applications in science and technology with IL have been proposed to date (Torimoto et al. 2010; Wasserscheid and Welton 2008; Eftekhari 2017). In 2006, it was reported that IL droplets could be observed by scanning electron microscopy (SEM) without charging behavior (Kuwabata et al. 2006). Subsequent efforts are being made to develop novel IL-based electron microscopy techniques to capitalize on the fact that a thin IL layer spread on insulating materials and biological...


Ionic liquid Transmission electron microscopy Biological specimens Kamlet-Taft parameters Herpes simplex virus type 1 



We thank Professor Yasuo Suda and Professor Masahiro Wakao (Kagoshima University, Japan) for their support in this research.

Compliance with ethical standards


This research was supported by Core Research for Evolution Science and Technology (CREST) from Japan Science and Technology Agency (JST) and from Senri Life Science Foundation in Japan.

Conflict of interest

Tetsuya Tsuda declares that he has no conflict of interest. Koshi Kawakami declares that he has no conflict of interest. Eiko Mochizuki declares that he has no conflict of interest. Susumu Kuwabata declares that he has no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by the author.


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Copyright information

© International Union for Pure and Applied Biophysics (IUPAB) and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Applied Chemistry, Graduate School of EngineeringOsaka UniversityOsakaJapan

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