Application of fluorescent Eu: Gd 2O 3 nanoparticles to the visualization of protein micropatterns

Dosi Dosev, Mikaela Nichkova, Maozi Liu, Bing Guo, Gang-yu Liu, Younan Xia, Bruce D. Hammock, Ian M. Kennedy

Research output: Chapter in Book/Report/Conference proceedingConference contribution

13 Scopus citations


Nanoparticles made of lanthanide oxides are promising fluorophores as a new class of tags in biochemistry because of their large Stokes shift, sharp emission spectra, long lifetime and lack of photobleaching. We demonstrate for first time the application of these nanoparticles to the visualization of protein micropatterns. Europium-doped gadolinium oxide (Eu:Gd 2O 3) nanoparticles were synthesized by spray pyrolysis and were characterized by means of laser-induced fluorescent spectroscopy and TEM. Their main emission peak is at 612 nm. And their size distribution is from 5 nm to 500 nm. The nanoparticles were coated with avidin through physical adsorption. Biotinylated Bovine Serum Albumin (BSA-b) was patterned on a silicon wafer using a micro-contact printing technique. The BSA-b - patterned wafer was incubated in a solution containing the avidin-coated nanoparticles. The specific interaction between biotin and avidin was studied by means of fluorescent microscopy and atomic-force microscopy (AFM). The fluorescent microscopic images revealed that the nanoparticles were organized into designated structures as defined by the microcontact printing process - non-specific binding of the avidin-coated nanoparticles to bare substrate was negligible. The fluorescent pattern did not suffer any photobleaching during the observation process which demonstrates the suitability of Eu:Gd 2O 3 nanoparticles as fluorescent labels with extended excitation periods - organic dyes, including chelates, suffer bleaching over the same period. More detailed studies were preformed using AFM at a single nanoparticle level. The specific and the non-specific binding densities of the particles were qualitatively evaluated.

Original languageEnglish (US)
Title of host publicationProgress in Biomedical Optics and Imaging - Proceedings of SPIE
EditorsD.V. Nicolau, J. Enderlein, R.C. Leif, D.L. Farkas, R. Raghavachari
Number of pages9
StatePublished - 2005
EventImaging, Manipulation, and Analysis of Biomolecules and Cells: Fundamentals and Applications III - San Jose, CA, United States
Duration: Jan 24 2005Jan 27 2005


OtherImaging, Manipulation, and Analysis of Biomolecules and Cells: Fundamentals and Applications III
Country/TerritoryUnited States
CitySan Jose, CA


  • AFM
  • Biosensor
  • Fluorescence
  • Lanthanide
  • Microcontact printing
  • Nanoparticles

ASJC Scopus subject areas

  • Engineering(all)


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