Biophysical Reviews

, Volume 10, Issue 3, pp 757–768 | Cite as

Interaction of proteins with ionic liquid, alcohol and DMSO and in situ generation of gold nano-clusters in a cell

  • Somen Nandi
  • Sridip Parui
  • Ritaban Halder
  • Biman Jana
  • Kankan Bhattacharyya


In this review, we give a brief overview on how the interaction of proteins with ionic liquids, alcohols and dimethyl sulfoxide (DMSO) influences the stability, conformational dynamics and function of proteins/enzymes. We present experimental results obtained from fluorescence correlation spectroscopy on the effect of ionic liquid or alcohol or DMSO on the size (more precisely, the diffusion constant) and conformational dynamics of lysozyme, cytochrome c and human serum albumin in aqueous solution. The interaction of ionic liquid with biomolecules (e.g. protein, DNA etc.) has emerged as a current frontier. We demonstrate that ionic liquids are excellent stabilizers of protein and DNA and, in some cases, cause refolding of a protein already denatured by chemical denaturing agents. We show that in ethanol–water binary mixture, proteins undergo non-monotonic changes in size and dynamics with increasing ethanol content. We also discuss the effect of water–DMSO mixture on the stability of proteins. We demonstrate how large-scale molecular dynamics simulations have revealed the molecular origin of this observed phenomenon and provide a microscopic picture of the immediate environment of the biomolecules. Finally, we describe how favorable interactions of ionic liquids may be utilized for in situ generation of fluorescent gold nano-clusters for imaging a live cell.


Binary mixture Conformational dynamics Folding/unfolding Ionic liquid MD simulation 



Biman Jana gratefully acknowledges the supercomputing facility CRAY at the Indian Association for the Cultivation of Science.


Thanks are due to the Department of Science and Technology J. C. Bose Fellowship for a generous research grant to Kankan Bhattacharyya and to the Council of Scientific and Industrial Research for awarding fellowships to Somen nandi, Sridip Parui and Ritaban Halder.

Compliance with Ethical Standards

Conflicts of interest

Somen Nandi, Sridip Parui, Ritaban Halder Biman jana and Kankan Bhattacharyya declare that they have no conflicts of interest regarding this work


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Copyright information

© International Union for Pure and Applied Biophysics (IUPAB) and Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Department of Physical Chemistry, Indian Association for the Cultivation of ScienceJadavpurKolkataIndia
  2. 2.Department of ChemistryIndian Institute of Science Education and Research BhopalBhopalIndia

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