Upconverting Phosphor Labels for Bioanalytical Assays

  • Terhi Riuttamäki (née Rantanen)Email author
  • Tero Soukka
Part of the Bioanalytical Reviews book series (BIOREV, volume 1)


Upconverting phosphors (UCPs) are photoluminescent inorganic crystals capable of photon upconversion upon absorption of two or more sequential photons. UCPs produce bright, structured emission at wavelengths shorter than the excitation radiation rendering them highly advanced labels for bioanalytical assays. The exceptional anti-Stokes emission allows total elimination of autofluorescence originating mainly from biomolecules and other sample components. UCPs are excited with near-infrared radiation which provides several advantages over ultraviolet excitation—including optimal penetration of biological material. This chapter summarizes the bioanalytical in vitro applications of UCPs and discusses the advantages and challenges of the emerging label technology. In addition, synthesis of the UCP labels and some of the instruments used for UCP detection are shortly reviewed. Bioimaging and therapeutic applications based on UCPs are outside of the scope of this chapter.


Bioanalytics Lanthanides Nanoparticles Near-infrared excitation Photon upconversion Upconverting phosphors 



Addition of photons by transfer of energy (upconversion mechanism)


Charge-coupled device (light detector)


Cetyltrimethylammonium bromide (cationic surfactant)


Ethylenediaminetetraacetic acid (chelating agent)


Enzyme-linked immunosorbent assay


Energy migration-mediated upconversion (upconversion mechanism)


Excited state absorption (upconversion mechanism)


Energy transfer upconversion (upconversion mechanism)


Free prostate-specific antigen (prostate cancer marker)


Ground-state absorption


Laser diode (excitation source)


Light emitting diode (excitation source)


Lateral flow (assay format)


Limit of detection


Limit of quantification


Lanthanide resonance energy transfer


Near-infrared radiation (wavelength 750–1,400 nm)


Photon avalanche (upconversion mechanism)


Photodiode (light detector)




Photomultiplier tube (light detector)


Point-of-care testing




Förster radius (the distance at which energy transfer efficiency is 50 %)


Resonance energy transfer (nonradiative energy transfer mechanism)


Staphylococcal enterotoxin B


Surface energy transfer (energy transfer to a metallic surface)


Transmission electron microscopy




Trioctylphosphine oxide


Upconverting phosphor (photoluminescent inorganic compound)


Upconversion resonance energy transfer


Ultraviolet radiation (wavelength <380 nm)



The authors wish to thank Dr. Paul Corstjens and Jan Slats (Leiden University Medical Center, the Netherlands) for microscopy examination of the PTIR550/F material. Financial support from the Research Executive Agency (REA) of the European Union under Grant Agreement number PITN-GA-2010-264772 (ITN CHEBANA) is gratefully acknowledged.


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Copyright information

© Springer International Publishing Switzerland 2013

Authors and Affiliations

  • Terhi Riuttamäki (née Rantanen)
    • 1
    • 2
    Email author
  • Tero Soukka
    • 1
  1. 1.Department of BiotechnologyUniversity of TurkuTurkuFinland
  2. 2.Kaivogen OyTurkuFinland

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