Journal of Fluorescence

, Volume 21, Issue 3, pp 937–944 | Cite as

Encapsulation of Hydrophobic Dyes in Polystyrene Micro- and Nanoparticles via Swelling Procedures

  • Thomas Behnke
  • Christian Würth
  • Katrin Hoffmann
  • Martin Hübner
  • Ulrich Panne
  • Ute Resch-GengerEmail author
Original Paper


Aiming at the derivation of a generalized procedure for the straightforward preparation of particles fluorescing in the visible and near-infrared (NIR) spectral region, different swelling procedures for the loading of the hydrophobic polarity-probe Nile Red into nano- and micrometer sized polystyrene particles were studied and compared with respect to the optical properties of the resulting particles. The effect of the amount of incorporated dye on the spectroscopic properties of the particles was investigated for differently sized beads with different surface chemistries, i.e., non-functionalized, amino-modified and PEG-grafted surfaces. Moreover, photostability and leaking studies were performed. The main criterion for the optimization of the dye loading procedures was a high and thermally and photochemically stable fluorescence output of the particles for the future application of these systems as fluorescent labels.


Fluorescence Nile Red Polystyrene Nanoparticles Microparticles Encapsulation Swelling 



We gratefully acknowledge financial support from the Federal Ministry of Economics and Technology (BMWI-22/06). We would also like to thank Mrs. M. Spieles for accurately technical assistance.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Thomas Behnke
    • 1
  • Christian Würth
    • 1
  • Katrin Hoffmann
    • 1
  • Martin Hübner
    • 1
  • Ulrich Panne
    • 1
  • Ute Resch-Genger
    • 1
    Email author
  1. 1.BAM Federal Institute for Materials Research and TestingBerlinGermany

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