Microparticle ratiometric oxygen sensors utilizing near-infrared emitting quantum dots. Academic Article uri icon


  • Luminescent sensors incorporating two luminophores, an indicator and a reference, offer many advantages over intensity measurements from sensors made with one indicator dye. Quantum dots have yet to be widely employed as insensitive reference luminophores in such systems. This work describes the use of near-infrared emitting quantum dots in conjunction with a long-lifetime platinum(II) porphyrin phosphor in a microsphere-based, ratiometric oxygen sensor. The process for self-assembly of the nanocomposite system was developed, and the response and photostability of the prototypes were investigated. Results indicate the sensors possess excellent sensitivity (K(SV) = 0.00826 M(-1)) at oxygen concentrations below 300 M and were resistant to photobleaching. The sensor luminophores displayed minimal spectral overlap and little interference from excitation light, preventing the need for optical filters. A reversible photoenhancement of the quantum dot signal was also observed when exposed for extended periods of time. This work demonstrates the advantages of incorporating long-wavelength quantum dots into ratiometric intensity sensing schemes and highlights some key limitations that must be considered in their use.

published proceedings

  • Analyst

altmetric score

  • 9

author list (cited authors)

  • Collier, B. B., Singh, S., & McShane, M.

citation count

  • 35

complete list of authors

  • Collier, Bradley B||Singh, Saurabh||McShane, Mike

publication date

  • March 2011