Phosphorescence probes can have significantly long lifetimes, on the order of micro- to milli-seconds or longer. In addition, environmental changes can affect the lifetimes of these phosphorescence probes. Thus, Phosphorescence Lifetime Imaging Microscopy (PLIM) is a very useful tool to localize the phosphorescence probes based on their lifetimes to study the variance in the lifetimes due to the micro environmental changes. Since the probes respond to the biologically relevant parameters like oxygen concentration, they can be used to study various biologically relevant processes like cellular metabolism, protein interaction etc. In this case, we study the effects of oxygen on Oxyphor G4 with PLIM. Since The Oxyphor G4 can be quenched by O₂, it is a good example of such a probe and has a lifetime around 250us. Here we present the digital frequency domain PLIM technique and study the lifetime of the Oxyphor G4 as a function of the O2 concentration. The lifetime data are successfully presented in a phasor plot for various O₂ concentrations and are consistent with the time domain data. Overall, we can analyze the oxygen consumption of varying cells using this technique.

Date Published: 21 February 2017
PDF: 8 pages
Proc. SPIE 10069, Multiphoton Microscopy in the Biomedical Sciences XVII, 1006918 (21 February 2017); doi: 10.1117/12.2255481

Published in SPIE Proceedings Vol. 10069:
Multiphoton Microscopy in the Biomedical Sciences XVII
Ammasi Periasamy; Peter T. C. So; Karsten König; Xiaoliang S. Xie, Editor(s)