Microchimica Acta

, Volume 172, Issue 3–4, pp 299–308 | Cite as

Mini-emulsion solvent evaporation: a simple and versatile way to magnetic nanosensors

  • Günter MistlbergerEmail author
  • Antonio L. Medina-Castillo
  • Sergey M. Borisov
  • Torsten Mayr
  • Alberto Fernández-Gutiérrez
  • Jorge F. Fernandez-Sanchez
  • Ingo Klimant
Original Paper


Magnetic optical sensor particles were prepared using a mini-emulsion solvent evaporation (MESE) technique. The resulting nanoparticles (NPs) have diameters around 100 nm and relatively narrow size distribution (PDI < 0.2). Incorporation of probes for oxygen or pH resulted in magnetic sensor particles for bioprocess monitoring and imaging applications. The MESE technique yields sensing NPs in higher quantities than obtained by a previously reported nanoprecipitation method, and the size of the NPs is smaller than that of particles made by spray-drying of sensor cocktails. Moreover, the technique is flexible in terms of polymers, solvents and indicators used in that it may be applied—at least in principle—to numerous combinations of two-phase systems.


Magnetic optical sensor particles Oxygen sensor pH sensor Light harvesting Miniemulsion solvent evaporation Nanosensor 



This work was supported by Österreichischer Austauschdienst, ÖAD (program Acciones Integradas) under the project number ES 13/2007. Further financial support was received from the Spanish Ministry of Education (FPU grant reference AP2006-01144) and the Regional Government of Andalusia (Excellence projects P07-FQM-02738 and P07-FQM-02625). We also thank Dr. Armin Zankel and Dr. Angelika Reichmann from the Institute for Electron Microscopy, Graz University of Technology, for the SEM measurements.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Günter Mistlberger
    • 1
    Email author
  • Antonio L. Medina-Castillo
    • 2
  • Sergey M. Borisov
    • 1
  • Torsten Mayr
    • 1
  • Alberto Fernández-Gutiérrez
    • 2
  • Jorge F. Fernandez-Sanchez
    • 2
  • Ingo Klimant
    • 1
  1. 1.Institute of Analytical Chemistry and Food ChemistryGraz University of TechnologyGrazAustria
  2. 2.Department of Analytical ChemistryUniversity of GranadaGranadaSpain

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