Abstract
We demonstrate sensitive spatially resolved detection of physiological chromophores that emit in the ultraviolet (<330 nm). An atypical laser source (a visible wavelength femtosecond optical parametric oscillator), and an unconventional collection geometry (a lensless detector that detects the forward-emitted fluorescence) enable this detection. We report the excitation spectra of the catecholamines dopamine and norepinephrine, together with near-UV emitters serotonin and tryptophan, in the range of 550–595 nm. We estimate the molecular two-photon action cross section of dopamine, norepinephrine, and serotonin to be 1.2 mGM (1 GM, or Goppert Mayor, is equal to 10-58 m4 s-1 photon-1), 2 mGM, and 43 mGM, respectively, at 560 nm. The sensitivity achieved by this method holds promise for the microscopic imaging of vesicular catecholamines in live cells.
© 2004 Optical Society of America
Full Article | PDF ArticleMore Like This
Guillermo A. Hernández-Mendoza, Dilia Aguirre-Olivas, Mario González-Gutiérrez, Héctor J. Leal, Naser Qureshi, Carlos G. Treviño-Palacios, Jorge Peón, and Francisco F. De-Miguel
Biomed. Opt. Express 11(3) 1432-1448 (2020)
Chunqiang Li, Riikka K. Pastila, Costas Pitsillides, Judith M. Runnels, Mehron Puoris’haag, Daniel Côté, and Charles P. Lin
Opt. Express 18(2) 988-999 (2010)
David W. Piston, Mark S. Kirby, Heping Cheng, W. J. Lederer, and Watt W. Webb
Appl. Opt. 33(4) 662-669 (1994)