Journal of Fluorescence

, Volume 17, Issue 2, pp 127–131

Metal Enhanced Fluorescence Solution-based Sensing Platform 2: Fluorescent Core-Shell Ag@SiO2 Nanoballs

  • Kadir Aslan
  • Meng Wu
  • Joseph R. Lakowicz
  • Chris D. Geddes
Short Communication


In this Rapid Communication, we present the development of monodisperse core-shell (silver core-silica shell) nanoparticles with various shell thicknesses featuring a fluorophore, subsequently named Metal-Enhanced Fluorescence (MEF) nanoballs. MEF nanoballs consist of a ≈130 nm silver nanoparticle core, a silica shell with up to 35 nm thickness and fluorophores doped within the silica shell. Fluorescent nanobubbles where the silver core is removed by chemical etching are used as control samples to show the benefits of using silver nanoparticles, i.e, Metal-Enhanced Fluorescence. Finally, we demonstrate the broad potential biological applications of MEF nanoballs by employing near-infra red emitting probes (Rhodamine 800) within the silica shell, for potential applications in cellular imaging and solution-based sensing.


Metal-enhanced fluorescence Radiative decay engineering Plasmon enhanced luminescence Plasmon enhanced fluorescence Surface enhanced fluorescence Fluorescence Plasmon Plasmonics Nanoparticles Silver nanoparticles Silver colloids Solution sensing platform 

Symbol and acronyms


Silver core, silica shell nanoparticles


Metal-Enhanced Fluorescence


Surface Plasmon Resonance


Rhodamine 800


Transmission Electron Microscope


Tetraethyl orthosilicate


  1. 1.
    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(1):55–62PubMedCrossRefGoogle Scholar
  2. 2.
    Geddes CD, Aslan K, Gryczynski I, Malicka J, Lakowicz JR, Noble Metal (2005) Nanostructure for metal-enhanced fluorescence. In: Review Chapter for Geddes CD, Aslan K, Gryczynski I, Malicka J, Lakowicz JR (eds) Radiative decay engineering, In topics in fluorescence in fluorescence spectroscopy. Kluwer Academic/Plenum Publishers, New York, USA, p 405Google Scholar
  3. 3.
    Malicka J, Gryczynski I, Kusba J, Lakowicz JR (2003) Effects of metallic silver island films on resonance energy transfer between Cy3 and Cy5-labeled DNA. Biopolymers 70:595–603PubMedCrossRefGoogle Scholar
  4. 4.
    Aslan K, Geddes CD (2005) Microwave-accelerated metal-enhanced fluorescence (MAMEF): A new platform technology for ultra-fast and ultra-bright assays. Anal Chem 77(24):8057–8067PubMedCrossRefGoogle Scholar
  5. 5.
    Aslan K, Huang J, Wilson GM, Geddes CD (2006) Metal-enhanced fluorescence-based RNA sensing. J Am Chem Soc 128:4206–4207PubMedCrossRefGoogle Scholar
  6. 6.
    Aslan K, Geddes CD (2006) Microwave-accelerated and metal-enhanced fluorescence myoglobin detection on silvered surfaces: Potential application to myocardial infarction diagnosis. Plasmonics 1(1):53–59CrossRefGoogle Scholar
  7. 7.
    Aslan K, Badugu R, Lakowicz JR, Geddes CD (2005) Metal-enhanced fluorescence from plastic substrates. J Fluores 15(2):99–104CrossRefGoogle Scholar
  8. 8.
    Aslan K, Holley P, Geddes CD (2006) Metal-enhanced fluorescence from silver nanoparticle-deposited polycarbonate substrates. J Mater Chem 16(27):2846–2857CrossRefGoogle Scholar
  9. 9.
    Geddes CD, Parfenov A, Roll D, Fang J, Lakowicz JR (2003) Electrochemical and laser deposition of silver for use in metal-enhanced fluorescence. Langmuir 19(15):6236–6241CrossRefGoogle Scholar
  10. 10.
    Aslan K, Szmacinski H, Lakowicz JR, Geddes CD (2004) Metal-enhanced fluorescence solution-based sensing platform. J Fluores 14:677–679CrossRefGoogle Scholar
  11. 11.
    Geddes CD (2002) Optical halide sensing using fluorescence quenching: Theory, simulations and applications-a review. Meas Sci Tech 12:R53–R88CrossRefGoogle Scholar
  12. 12.
    Aslan K, Leonenko Z, Lakowicz JR, Geddes CD (2005) Annealed silver-island films for applications in metal-enhanced fluorescence: Interpretation in terms of radiating plasmons. J Fluores 15:643–654CrossRefGoogle Scholar
  13. 13.
    Kobayashi Y, Katakami H, Mine E, Nagao D, Konno M, Liz-Marzan LM (2005) Silica coating of silver nanoparticles using a modified Stober method. J Coll Inter Sci 283(2):392–396CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Kadir Aslan
    • 1
  • Meng Wu
    • 2
  • Joseph R. Lakowicz
    • 2
  • Chris D. Geddes
    • 1
    • 2
  1. 1.Institute of Fluorescence, Laboratory for Advanced Medical Plasmonics, Medical Biotechnology CenterUniversity of Maryland Biotechnology InstituteBaltimoreUSA
  2. 2.Center for Fluorescence SpectroscopyUniversity of Maryland School of MedicineBaltimoreUSA

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