Expansion of intensity correlation spectroscopy for lifetime measurements--application to intracellular oxygen dynamics measurements.
We report on a simple correlation method for lifetime measurements using a random modulated excitation light source. We use an intensity correlation function of emission for lifetime analyses. In this method, no reference timing of the excitation is required. We apply the correlation method to measure phosphorescence decays and successfully demonstrate in the analysis of the phosphorescence decay from Pd(II) porphine in HeLa cells under aerobic and anaerobic conditions to understand the oxygen dynamics in individual cells. The method is applicable to faster decay time measurements down to a nanosecond range when the detection system is improved. Current fluorescence correlation setups can easily be modified for lifetime measurements, expanding the applicability in biological problems.
Nishimura
Goro
G
Hokkaido University, Biophysics Laboratory, Research Institute for Electronic Science, Sapporo 060-0812, JapanHokkaido University, Topological Science and Technology, The 21st COE program, Sapporo 060-8628, Japan. gnishi@imd.es.hokudai.ac.jp
Pack
Changi
C
Tamura
Mamoru
M
D000465:Algorithms; D006367:HeLa Cells; D006801:Humans; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*
D010100:Oxygen