Jump to main content
Jump to site search


Amplified vibrational circular dichroism as a manifestation of the interaction between a water soluble gold nanocluster and cobalt salt

Author affiliations

Abstract

Vibrational circular dichroism (VCD) is a powerful tool for the structure determination of dissolved molecules. However, the application of VCD to nanostructures is limited up to now due to the weakness of the effect and hence the low signal intensities. Here we show that the addition of a small amount of cobalt(II) drastically enhances the VCD signals of a thiolate-protected gold cluster Au25(Capt)18 (Capt = captopril) in aqueous solution. An increase of VCD signal intensity of at least one order of magnitude is observed. The enhancement depends on the amount of CoCl2 added but almost an order of magnitude enhancement is already observed at a cluster : CoCl2 ratio of 1 : 1. In contrast, circular dichroism (CD) and infrared spectra hardly change. The increase in VCD intensity goes along with a qualitative change of the spectrum and the enhancement increases with time reaching a stable state only after several hours. The enhancement is due to an interaction between the cobalt(II) and the cluster, which also leads to quenching of its fluorescence. The behaviour is completely different for free captopril, where the addition of cobalt(II) salt does not affect the VCD spectrum.

Graphical abstract: Amplified vibrational circular dichroism as a manifestation of the interaction between a water soluble gold nanocluster and cobalt salt

Back to tab navigation

Supplementary files

Publication details

The article was received on 31 Aug 2019, accepted on 09 Nov 2019 and first published on 11 Nov 2019


Article type: Paper
DOI: 10.1039/C9NR07534H
Nanoscale, 2019, Advance Article
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    Amplified vibrational circular dichroism as a manifestation of the interaction between a water soluble gold nanocluster and cobalt salt

    S. Roy Bhattacharya and T. Bürgi, Nanoscale, 2019, Advance Article , DOI: 10.1039/C9NR07534H

    This article is licensed under a Creative Commons Attribution-NonCommercial 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 and it is not used for commercial purposes.

    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