Jump to main content
Jump to site search

Issue 46, 2016
Previous Article Next Article

Stabilizing effect of TMAO on globular PNIPAM states: preferential attraction induces preferential hydration

Author affiliations

Abstract

We study the effect of the organic co-solute trimethylamine N-oxide (TMAO) on the volume phase transition of microgel particles made from poly(N-isopropylacrylamide) (PNIPAM) using dynamic light scattering (DLS) and all-atom molecular dynamics (MD) simulations. The DLS measurements reveal a continuous TMAO-induced shrinking process from a coil to a globular state of PNIPAM microgel particles. Analyzing the DLS data by the phenomenological Flory–Rehner theory verifies the stabilization of the globular state of the particles in the presence of TMAO. Complementary atomistic MD simulations highlight a pronounced accumulation of TMAO molecules around PNIPAM chains. We observe a significant preferential attraction between TMAO and the globular state of PNIPAM, which is additionally stabilized by a larger number of hydrating water molecules compared to pure aqueous solutions. Further DLS measurements were also conducted on PNIPAM suspensions with the co-solute urea added. The observed differences compared with the results obtained for TMAO support the proposed mechanism.

Graphical abstract: Stabilizing effect of TMAO on globular PNIPAM states: preferential attraction induces preferential hydration

Back to tab navigation

Supplementary files

Publication details

The article was received on 30 Aug 2016, accepted on 03 Nov 2016 and first published on 03 Nov 2016


Article type: Paper
DOI: 10.1039/C6CP05991K
Phys. Chem. Chem. Phys., 2016,18, 31459-31470
  • Open access: Creative Commons BY license
  •   Request permissions

    Stabilizing effect of TMAO on globular PNIPAM states: preferential attraction induces preferential hydration

    M. A. Schroer, J. Michalowsky, B. Fischer, J. Smiatek and G. Grübel, Phys. Chem. Chem. Phys., 2016, 18, 31459
    DOI: 10.1039/C6CP05991K

    This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements