Quantification of fluorophore concentration in tissue-simulating media by fluorescence measurements with a single optical fiber.
Quantifying fluorescent compounds in turbid media such as tissue is made difficult by the effects of multiple scattering and absorption of the excitation and emission light. The approach that we used was to measure fluorescence using a single 200-microm optical fiber as both the illumination source and the detector. Fluorescence of aluminum phthalocyanine tetrasulfonate (AlPcS4) was measured over a wide range of fluorophore concentrations and optical properties in tissue-simulating phantoms. A root-mean-square accuracy of 10.6% in AlPcS4 concentration was attainable when fluorescence was measured either interstitially or at the phantom surface. The individual effects of scattering, absorption, and the scattering phase function on the fluorescence signal were also studied by experiments and Monte Carlo simulations.
Diamond
Kevin R
KR
Department of Medical Physics, Hamilton Regional Cancer Centre and McMaster University, Concession Street, Hamilton, Ontario L8V 5C2, Canada. kevin.diamond@hrcc.on.ca
Patterson
Michael S
MS
Farrell
Thomas J
TJ
D000042:Absorption; D005336:Fiber Optic Technology; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000032:analysis*; D007211:Indoles / Q000032:analysis; D009010:Monte Carlo Method; D055100:Optical Fibers; D009942:Organometallic Compounds / Q000032:analysis; D009994:Osmolar Concentration; D012542:Scattering, Radiation; D012996:Solutions / Q000737:chemistry
D005456:Fluorescent Dyes; D007211:Indoles; D009942:Organometallic Compounds; D012996:Solutions; C048577:aluminum tetrasulfophthalocyanine