title: A novel frequency domain fluorescence technique for determination of triplet decay times.
abstract: Frequency domain fluorescence measurement using two diode lasers with amplitude modulation in the kHz range yields a signal component at the sum frequency. This intermodulation phenomenon was observed in an aqueous solution of haematoporphyrin (HP) and could be related to triplet state population kinetics. This indirect measurement technique may allow triplet decay time measurement during photodynamic therapy (PDT) enabling monitoring of the type II phototoxic damage rate.
authors.affiliation: Department of Radiotherapy, Daniel den Hoed Cancer Centre, University Hospital Rotterdam, The Netherlands. sterenborg@kfih.azr.nl
authors.forename: H J
authors.initials: HJ
authors.lastname: Sterenborg
authors.forename: M E
authors.initials: ME
authors.lastname: Janson
authors.forename: M J
authors.initials: MJ
authors.lastname: van Gemert
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D005453:Fluorescence; D006415:Hematoporphyrins; D006801:Humans; D007834:Lasers; D008962:Models, Theoretical; D009369:Neoplasms / Q000188:drug therapy; D010778:Photochemotherapy / Q000706:statistics & numerical data; D012996:Solutions; D014867:Water
chemical_list: D006415:Hematoporphyrins; D012996:Solutions; D014867:Water