, Volume 6, Issue 1, pp 125–132 | Cite as

Investigating Fluorescence Quenching of ZnS Quantum Dots by Silver Nanoparticles



Water dispersible zinc sulfide quantum dots (ZnS QDs) with an average diameter of 2.9 nm were synthesized in an environment friendly method using chitosan as stabilizing agent. These nanocrystals displayed characteristic absorption and emission spectra having an absorbance edge at 300 nm and emission maxima (λemission) at 427 nm. Citrate-capped silver nanoparticles (Ag NPs) of ca. 37-nm diameter were prepared by modified Turkevich process. The fluorescence of ZnS QDs was significantly quenched in presence of Ag NPs in a concentration-dependent manner with Ksv value of 9 × 109 M−1. The quenching mechanism was analyzed using Stern–Volmer plot which indicated mixed nature of quenching. Static mechanism was evident from the formation of electrostatic complex between positively charged ZnS QDs and negatively charged Ag NPs as confirmed by absorbance study. Due to excellent overlap between ZnS QDs emission and surface plasmon resonance band of Ag NPs, the role of energy transfer process as an additional quenching mechanism was investigated by time-resolved fluorescence measurements. Time-correlated single-photon counting study demonstrated decrease in average lifetime of ZnS QDs fluorescence in presence of Ag NPs. The corresponding Förster distance for the present QD–NP pair was calculated to be 18.4 nm.


ZnS QDs Ag NPs Fluorescence quenching Energy transfer 


  1. 1.
    Zhong W (2009) Nanomaterials in fluorescence-based biosensing. Anal Bioanal Chem 394:47–59CrossRefGoogle Scholar
  2. 2.
    Alivisatos AP (1996) Perspectives on the physical chemistry of semiconductor nanocrystals. J Phys Chem 100:13226–13239CrossRefGoogle Scholar
  3. 3.
    Smith AM, Ruan G, Rhyner MN, Nie S (2006) Engineering luminescent quantum dots for in vivo molecular and cellular imaging. Anal Biomed Eng 34:3–14CrossRefGoogle Scholar
  4. 4.
    Medintz IL, Uyeda HT, Goldman ER, Mattoussi H (2005) Quantum dot bioconjugates for imaging, labelling and sensing. Nat Mater 4:435–446CrossRefGoogle Scholar
  5. 5.
    Han M, Gao X, Su JZ, Nie S (2001) Quantum-dot-tagged microbeads for multiplexed optical coding of biomolecules. Nat Biotechnol 19:631–635CrossRefGoogle Scholar
  6. 6.
    Alviastos P (2004) The use of nanocrystals in biological detection. Nat Biotechnol 22:47–52CrossRefGoogle Scholar
  7. 7.
    Jamieson T, Bakhshi R, Petrova D, Pocock R, Imani M, Seifalian AM (2007) Biological applications of quantum dots. Biomaterials 28:4717–4732CrossRefGoogle Scholar
  8. 8.
    Li X, Qian J, Jiang L, He S (2009) Fluorescence quenching of quantum dots by gold nanorods and its application to DNA detection. Appl Phys Lett 94:063111–063113CrossRefGoogle Scholar
  9. 9.
    Dyadyusha L, Yin H, Jaiswal S, Brown T, Baumberg JJ, Booy FP, Melvin T (2005) Quenching of CdSe quantum dot emission, a new approach for biosensing. Chem Commun 25:3201–3203CrossRefGoogle Scholar
  10. 10.
    Willard DM, Orden AV (2003) Quantum dots: resonant energy-transfer sensor. Nat Mater 2:575–576CrossRefGoogle Scholar
  11. 11.
    Medintz IL, Clapp AR, Mattoussi H, Goldman ER, Fisher B, Mauro JM (2003) Self-assembled nanoscale biosensors based on quantum dot FRET donors. Nat Mater 2:630–638CrossRefGoogle Scholar
  12. 12.
    Ray K, Badugu R, Lakowicz JR (2006) Metal-enhanced fluorescence from CdTe nanocrystals: a single-molecule fluorescence study. J Am Chem Soc 128:8998–8999CrossRefGoogle Scholar
  13. 13.
    Dulkeith E, Ringler M, Klar TA, Feldmann J, Javier AM, Parak WJ (2005) Gold nanoparticles quench fluorescence by phase induced radiative rate suppression. Nano Lett 5:585–589CrossRefGoogle Scholar
  14. 14.
    Murgadoss A, Chattopadhyay A (2008) Tuning photoluminescence of ZnS nanoparticles by silver. Bull Mater Sci 31:533–539CrossRefGoogle Scholar
  15. 15.
    Zhang J, Fu Y, Chowdhury MH, Lakowicz JR (2007) Metal-enhanced single-molecule fluorescence on silver particle monomer and dimer: coupling effect between metal particles. Nano Lett 7:2101–2107CrossRefGoogle Scholar
  16. 16.
    Pompa PP, Martiradonna L, Torre AD, Sala FD, Manna L, Vittorio MD, Calabi F, Cingolani R, Rinaldi R (2006) Metal-enhanced fluorescence of colloidal nanocrystals with nanoscale control. Nat Nanotechnol 1:126–130CrossRefGoogle Scholar
  17. 17.
    Aslan K, Gryczynski I, Malicka J, Matveeva E, Lakowicz JR, Geddes CD (2005) Metal-enhanced fluorescence: an emerging tool in biotechnology. Curr Opin Biotechnol 16:55–62CrossRefGoogle Scholar
  18. 18.
    Aslan K, Lakowicz JR, Geddes CD (2005) Metal-enhanced fluorescence using anisotropic silver nanostructures:critical progress to date. Anal Bioanal Chem 382:926–933CrossRefGoogle Scholar
  19. 19.
    Sabatini CA, Pereira RV, Gehlen MH (2007) Fluorescence modulation of acridine and coumarin dyes by silver nanoparticles. J Fluoresc 17:377–382CrossRefGoogle Scholar
  20. 20.
    Nabika H, Deki S (2003) Enhancing and quenching functions of silver nanoparticles on the luminescent properties of europium complex in the solution phase. J Phys Chem B 107:9161–9164CrossRefGoogle Scholar
  21. 21.
    Tay LL, Rowell N, Boukherroub R (2005) Colloidal silver nanoparticle induced photoluminescence quench on the surface functionalized planar si. Mater Res Soc 901:221Google Scholar
  22. 22.
    Umadevi M, Vanelle P, Terme T, Rajkumar BJM, Ramakrishnan V (2009) Fluorescence quenching of 1, 4-Dihydroxy-2, 3-Dimethyl-9, 10-anthraquinone by silver nanoparticles: size effect. J Fluoresc 19:3–10CrossRefGoogle Scholar
  23. 23.
    Zhang J, Fu Y, Chowdhury MH, Lakowicz JR (2007) Enhanced Förster resonance energy transfer on single metal particle. 2. dependence on donor − acceptor separation distance, particle size, and distance from metal surface. J Phys Chem C 111:11784–11792CrossRefGoogle Scholar
  24. 24.
    Yun CS, Javier A, Jennings T, Fisher M, Hira S, Peterson S, Hopkins B, Reich NO, Strouse GF (2005) Nanometal surface energy transfer in optical rulers, breaking the FRET barrier. J Am Chem Soc 127:3115–3119CrossRefGoogle Scholar
  25. 25.
    Saini S, Bhowmick S, Shenoy VB, Bagchi B (2007) Rate of excitation energy transfer between fluorescent dyes and nanoparticles. J Photochem Photobiol A Chem 190:335–341CrossRefGoogle Scholar
  26. 26.
    H. C. Warad, C. Thanachayanont, G. Tumcharern, J. Dutta, (2007) Proceedings of the 2nd IEEE International Conference on Nano/Micro Engineered and Molecular System; Bangkok Thailand.Google Scholar
  27. 27.
    Williams ATR, Winfield SA, Miller JN (1983) Relative fluorescence quantum yields using a computer-controlled luminescence spectrometer. Analyst 108:1067–1071CrossRefGoogle Scholar
  28. 28.
    Lakowicz JR (1999) Principles of fluorescence spectroscopy, 3 rdth edn. Kluwer/Plenum, New YorkGoogle Scholar
  29. 29.
    Turkevich J, Stevenson PC, Hillier J (1951) A study of the nucleation and growth processes in the synthesis of colloidal gold, John Turkevich Discuss. Faraday Soc 11:55–75CrossRefGoogle Scholar
  30. 30.
    Xiao Q, Xiao C (2008) Synthesis and photoluminescence of water-soluble Mn2 + -doped ZnS quantum dots. Appl Surf Sci 254:6432–6435CrossRefGoogle Scholar
  31. 31.
    Lippens PE, Lannoo M (1989) Calculation of the band gap for small CdS and ZnS crystallites. Phys Rev B 39:10935–10942CrossRefGoogle Scholar
  32. 32.
    Brus L (1986) Electronic wave functions in semiconductor clusters: experiment and theory. J Phys Chem 90:2555–2560CrossRefGoogle Scholar
  33. 33.
    Mall M, Kumar L (2010) Optical studies of Cd2+ and Mn2+ Co-doped ZnS nanocrystals. J Lumin 130:660–665CrossRefGoogle Scholar
  34. 34.
    Sapra S, Prakash A, Ghangrekar A, Periasamy N, Sarma DD (2005) Emission properties of manganese-doped ZnS nanocrystals. J Phys Chem B 109:1663–1668CrossRefGoogle Scholar
  35. 35.
    Pillai ZS, Kamat PV (2004) What factors control the size and shape of silver nanoparticles in the citrate ion reduction method. J Phys Chem B 108:945–951CrossRefGoogle Scholar
  36. 36.
    Puebla RAA, Aroca RF (2009) Synthesis of silver nanoparticles with controllable surface charge and their application to surface-enhanced Raman scattering. Anal Chem 81:2280–2285CrossRefGoogle Scholar
  37. 37.
    Fan C, Wang S, Hong JW, Bazan GC, Plazco KW, Heeger AJ (2003) Beyond superquenching: hyper-efficient energy transfer from conjugated polymers to gold nanoparticles. PNAS 100:6297–6301CrossRefGoogle Scholar
  38. 38.
    Longa D, Wua G, Chen S (2007) Preparation of oligochitosan stabilized silver nanoparticles by gamma irradiation. Radiat Phys Chem 76:1126–1131CrossRefGoogle Scholar
  39. 39.
    Tan WB, Huang N, Zhang Y (2007) Ultrafine biocompatible chitosan nanoparticles encapsulating multi-coloured quantum dots for bioapplications. J Colloid Interface Sci 310:464–470CrossRefGoogle Scholar
  40. 40.
    O'Connella MJ, Chana CK, Lia W, Hicksa RK, Doorna SK, Wang HL (2007) Polyelectrolyte platform for sensitive detection of biological analytes via reversible fluorescence quenching. Polymer 48:7582–7589CrossRefGoogle Scholar
  41. 41.
    Ghosh SK, Pal A, Kundu S, Nath S, Pal T (2004) Fluorescence quenching of 1-methylaminopyrene near gold nanoparticles: size regime dependence of the small metallic particles. Chem Phys Lett 395:366–372CrossRefGoogle Scholar
  42. 42.
    Griffin J, Singh AK, Senapati D, Rhodes P, Mitchell K, Robinson B, Yu E, Ray PC (2008) Size- and distance-dependent nanoparticle surface-energy transfer (NSET) method for selective sensing of hepatitis C virus RNA. Chem Eur J 15:342–351CrossRefGoogle Scholar
  43. 43.
    Sarkar S, Bose R, Jana S, Jana NR, Pradhan N (2010) Doped semiconductor nanocrystals and organic dyes: an efficient and greener FRET system. J Phys Chem Lett 1:636–640CrossRefGoogle Scholar
  44. 44.
    Huang F, Lerner E, Sato S, Amir D, Haas E, Fersht AR (2009) Time-resolved fluorescence resonance energy transfer study shows a compact denatured state of the B domain of protein A. Biochemistry 48:3468–3476CrossRefGoogle Scholar
  45. 45.
    Williams G, Kamat PV (2009) Graphene − semiconductor nanocomposites: excited-state interactions between ZnO nanoparticles and graphene oxide. Langmuir 25:13869–13873CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of Biotechnology, Indian Institute of Technology GuwahatiGuwahati-39India
  2. 2.Centre for Nanotechnology, Indian Institute of Technology GuwahatiGuwahati-39India
  3. 3.Department of Chemistry, Indian Institute of Technology GuwahatiGuwahati-39India

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