title: Femtosecond two-photon excited fluorescence of melanin.
abstract: Fluorescence of synthetic melanin in dimethyl sulfoxide has been excited by two-photon absorption at 800 nm, using 120 fs pulses with photon flux densities > or = 10(27) cm-2 s-1. The shortest main component of the three-exponential decay of fluorescence is 200 +/- 2 ps. The overall spectral shape is red-shifted with respect to the 400 nm excited fluorescence. Two-photon excited melanin fluorescence also has been measured from excised samples of healthy human skin tissue. Because of the selectivity of melanin excitation via resonant two-photon absorption, it is hypothesized that fluorescence excited in this way may yield information on malignant transformation.
authors.affiliation: Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, Berlin, Germany. teuchner@mbi-berlin.de
authors.forename: K
authors.initials: K
authors.lastname: Teuchner
authors.forename: W
authors.initials: W
authors.lastname: Freyer
authors.forename: D
authors.initials: D
authors.lastname: Leupold
authors.forename: A
authors.initials: A
authors.lastname: Volkmer
authors.forename: D J
authors.initials: DJ
authors.lastname: Birch
authors.forename: P
authors.initials: P
authors.lastname: Altmeyer
authors.forename: M
authors.initials: M
authors.lastname: Stücker
authors.forename: K
authors.initials: K
authors.lastname: Hoffmann
mesh_terms: D006801:Humans; D066298:In Vitro Techniques; D008543:Melanins / Q000138:chemical synthesis / Q000737:chemistry / Q000528:radiation effects*; D008545:Melanoma / Q000209:etiology; D010777:Photochemistry; D017785:Photons; D012867:Skin / Q000737:chemistry / Q000528:radiation effects; D012878:Skin Neoplasms / Q000209:etiology; D013050:Spectrometry, Fluorescence
chemical_list: D008543:Melanins