Journal of Fluorescence

, Volume 24, Issue 3, pp 745–750 | Cite as

Fluorescence Spectroscopy and Confocal Microscopy of the Mycotoxin Citrinin in Condensed Phase and Hydrogel Films

  • Milena H. Lauer
  • Marcelo H. GehlenEmail author
  • Karen de Jesus
  • Roberto G. S. Berlinck


The emission spectra, quantum yields and fluorescence lifetimes of citrinin in organic solvents and hydrogel films have been determined. Citrinin shows complex fluorescence decays due to the presence of two tautomers in solution and interconversion from excited-state double proton transfer (ESDPT) process. The fluorescence decay times associated with the two tautomers have values near 1 and 5 ns depending on the medium. In hydrogel films of agarose and alginate, fluorescence imaging showed that citrinin is not homogeneously dispersed and highly emissive micrometer spots may be formed. Fluorescence spectrum and decay analysis are used to recognize the presence of citrinin in hydrogel films using confocal fluorescence microscopy and spectroscopy.


Citrinin Natural product Emission decay Fluorescence imaging 



Financial support for fluorescence microscopy instrumentation was provided by FAPESP research grant 2011/18215-8. RGSB thanks to FAPESP for financial support (BIOTA/BIOprospecTA research grant 2010/50190-2). MHL thanks to FAPESP for a doctoral fellowship and KJ thanks to CAPES for a MSc scholarship. We thank to Professor Dr Johan Hofkens and Dr Kris P. F. Janssen for the use of SIS image software from the MDS Laboratory of the Department of Chemistry, Katholieke Universiteit Leuven.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Milena H. Lauer
    • 1
  • Marcelo H. Gehlen
    • 1
    Email author
  • Karen de Jesus
    • 1
  • Roberto G. S. Berlinck
    • 1
  1. 1.Instituto de Química de São Carlos – Universidade de São PauloSão CarlosBrazil

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