Journal of Chemical Sciences

, 130:143 | Cite as

Glutathione-capped gold nanoclusters: photoinduced energy transfer and singlet oxygen generation\(^{\S }\)

  • Christian Talavera
  • Prashant V KamatEmail author
Regular Article


Glutathione-capped gold clusters prepared in an aqueous medium are known to exhibit excellent photosensitizing properties. We have now successfully transferred these gold clusters in an organic medium while retaining all the characteristic excited state properties. These gold clusters can be further modified with organic ligands such as 2-Phenylethanethiol (PET). The gold clusters in organic medium exhibit enhanced emission yield (\(\Phi _{\mathrm{f}} = 0.15\)) compared to that in an aqueous medium (\(\Phi _{\mathrm{f}} = 0.08\)). The excited state lifetimes of \(3.7\,\upmu \hbox {s}\) (untreated) and \(1.5\,\upmu \hbox {s}\) (PET treated) in toluene are also greater than the lifetime observed in aqueous solution (\(0.77\,\upmu \hbox {s}\)). By employing laser flash photolysis we are able to induce triplet energy transfer to \(\upbeta \)-carotene and oxygen. A singlet oxygen generation with the efficiency of 13% was observed in these experiments. The excited state properties of glutathione-capped gold clusters further shows its importance as a photosensitizer in light energy conversion and biomedical applications

Graphical Abstract

SYNOPSIS A few atom gold clusters modified with organic ligands exhibit high photoactivity by generating singlet oxygen with 13% quantum efficiency.


Gold clusters singlet oxygen excited state transient absorption specroscopy energy transfer photosensitizer 



The research work described here was supported by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences of the U.S. Department of Energy, through award DE-FC02-04ER15533. This is contribution number NDRL No. 5218 from the Notre Dame Radiation Laboratory.

Supplementary material

12039_2018_1549_MOESM1_ESM.pdf (825 kb)
Supplementary material 1 (pdf 824 KB)


  1. 1.
    Li G and Jin R 2013 Atomically precise gold nanoclusters as new model catalysts Acc. Chem. Res. 46 1749CrossRefGoogle Scholar
  2. 2.
    Abbas M A, Kamat P V and Bang J H 2018 Thiolated gold nanoclusters for light energy conversion ACS Energy Lett. 3 840CrossRefGoogle Scholar
  3. 3.
    Stamplecoskie K G, Chen Y-S and Kamat P V 2014 Excited-state behavior of luminescent glutathione-protected gold clusters J. Phys. Chem. C 118 1370CrossRefGoogle Scholar
  4. 4.
    Ohta T, Shibuta M, Tsunoyama H, Negishi Y, Eguchi T and Nakajima A 2013 Size and structure dependence of electronic states in thiolate-protected gold nanoclusters of Au25(SR)18, Au38(SR)24, and Au144(SR)60 J. Phys. Chem. C 117 3674CrossRefGoogle Scholar
  5. 5.
    Qian H, Zhu M, Wu Z and Jin R 2012 Quantum sized gold nanoclusters with atomic precision Acc. Chem. Res. 45 1470CrossRefGoogle Scholar
  6. 6.
    Jin R, Qian H, Wu Z, Zhu Y, Zhu M, Mohanty A and Garg N 2010 Size focusing: A methodology for synthesizing atomically precise gold nanoclusters J. Phys. Chem. Lett. 1 2903CrossRefGoogle Scholar
  7. 7.
    Zhu M, Qian H and Jin R 2010 Thiolate-protected Au\(_{24}\)(SC\(_{2}\)H\(_{4}\)Ph)\(_{20}\) nanoclusters: Superatoms or not? J. Phys. Chem. Lett. 1 1003CrossRefGoogle Scholar
  8. 8.
    Chen Y-S, Choi H and Kamat P V 2013 Metal cluster sensitized solar cells. A new class of thiolated gold sensitizers delivering efficiency greater than 2% J. Am. Chem. Soc. 135 8822CrossRefGoogle Scholar
  9. 9.
    Chen Y-S and Kamat P V 2014 Glutathione capped gold nanoclusters as photosensitizers. Visible light induced hydrogen generation in neutral water J. Am. Chem. Soc. 136 6075CrossRefGoogle Scholar
  10. 10.
    Choi H, Chen Y-S, Stamplecoskie K G and Kamat P V 2015 Boosting the photovoltage of dye-sensitized solar cells with thiolated gold nanoclusters J. Phys. Chem. Lett. 6 217CrossRefGoogle Scholar
  11. 11.
    Stamplecoskie K G and Kamat P V 2015 Synergistic Effects in the Coupling of Plasmon Resonance of Metal Nanoparticles with Excited Gold Clusters J. Phys. Chem. Lett. 1870CrossRefGoogle Scholar
  12. 12.
    Stamplecoskie K G and Kamat P V 2014 Size-dependent excited state behavior of glutathione-capped gold clusters and their light-harvesting capacity J. Am. Chem. Soc. 136 11093CrossRefGoogle Scholar
  13. 13.
    Yu Y, Chen X, Yao Q, Yu Y, Yan N and Xie J 2013 Scalable and Precise Synthesis of Thiolated \(\text{ Au }_{10-12}, \text{ Au }_{15}, \text{ Au }_{18}\), and \(\text{ Au }_{25}\) Nanoclusters via pH Controlled CO Reduction Chem. Mater. 25 946CrossRefGoogle Scholar
  14. 14.
    Brust M, Walker M, Bethell D, Schffrin D J and Whyman R 1994 Synthesis of thiol-derivatized gold nanoparticles in a two-phase liquid-liquid system Chem. Commun. 801Google Scholar
  15. 15.
    Brust M, Fink J, Bethell D, Schiffrin D J and Kiely C 1995 Synthesis and reactions of functionalized gold nanoparticles J. Chem. Soc. Chem. Comm. 1655Google Scholar
  16. 16.
    Thomas K G, Zajicek J and Kamat P V 2002 Surface binding properties of tetraoctylammomium bromide capped gold nanoparticles Langmuir 18 3722CrossRefGoogle Scholar
  17. 17.
    Luo Z T, Yuan X, Yu Y, Zhang Q B, Leong D T, Lee J Y and Xie J P 2012 From aggregation-induced emission of Au(I)-thiolate complexes to ultrabright Au(0)@Au(I)-thiolate core-shell nanoclusters J. Am. Chem. Soc. 134 16662CrossRefGoogle Scholar
  18. 18.
    Lambert C and Redmond R W 1994 Triplet energy level of \(\upbeta \)-carotene Chem. Phys. Lett. 228 495CrossRefGoogle Scholar
  19. 19.
    Nielsen B R, Jørgensen K and Skibsted L H 1998 Triplet–triplet extinction coefficients, rate constants of triplet decay and rate constant of anthracene triplet sensitization by laser flash photolysis of astaxanthin, \(\upbeta \)-carotene, canthaxanthin and zeaxanthin in deaerated toluene at 298 K J. Photochem. Photobiol. A: Chem. 112 127CrossRefGoogle Scholar
  20. 20.
    Zhang X-F and Li X 2011 The photostability and fluorescence properties of diphenylisobenzofuran J. Lumin. 131 2263CrossRefGoogle Scholar
  21. 21.
    Chadwick S J, Salah D, Livesey P M, Brust M and Volk M 2016 Singlet oxygen generation by laser irradiation of gold nanoparticles J. Phys. Chem. C 120 10647CrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  1. 1.Radiation Laboratory, Department of Chemistry and BiochemistryUniversity of Notre DameNotre DameUSA

Personalised recommendations