Nano Research

, Volume 1, Issue 4, pp 333–340 | Cite as

Two distinct fluorescent quantum clusters of gold starting from metallic nanoparticles by pH-dependent ligand etching

  • Madathumpady Abubaker Habeeb Muhammed
  • Subramani Ramesh
  • Sudarson Sekhar Sinha
  • Samir Kumar Pal
  • Thalappil Pradeep
Open Access
Research Article


Two fluorescent quantum clusters of gold, namely Au25 and Au8, have been synthesized from mercaptosuccinic acid-protected gold nanoparticles of 4–5 nm core diameter by etching with excess glutathione. While etching at pH ∼3 yielded Au25, that at pH 7–8 yielded Au8. This is the first report of the synthesis of two quantum clusters starting from a single precursor. This simple method makes it possible to synthesize well-defined clusters in gram quantities. Since these clusters are highly fluorescent and are highly biocompatible due to their low metallic content, they can be used for diagnostic applications.


Gold cluster glutathione pH ligand etching fluorescence 

Supplementary material

12274_2008_8035_MOESM1_ESM.pdf (661 kb)
Supplementary material, approximately 664 KB.


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Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Madathumpady Abubaker Habeeb Muhammed
    • 1
  • Subramani Ramesh
    • 1
  • Sudarson Sekhar Sinha
    • 2
  • Samir Kumar Pal
    • 2
  • Thalappil Pradeep
    • 1
  1. 1.DST Unit on Nanoscience (DST UNS), Department of Chemistry and Sophisticated Analytical Instrument FacilityIndian Institute of Technology MadrasChennaiIndia
  2. 2.Unit for Nanoscience and Technology, Department of Chemical, Biological and Macromolecular SciencesSatyendra Nath Bose National Centre for Basic SciencesKolkataIndia

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