title: Intravital multiphoton photoconversion with a cell membrane dye.
abstract: Photoconversion, an irreversible shift in a fluorophore emission spectrum after light exposure, is a powerful tool for marking cellular and subcellular compartments and tracking their dynamics in vivo. This paper reports on the photoconversion properties of Di-8-ANEPPS, a commercially available membrane dye. When illuminated with near-infrared femtosecond laser pulses, Di-8-ANEPPS undergoes multiphoton photoconversion as indicated by the supralinear dependence of the conversion rate ρpcon the incident power (ρpc∝Iexc2.27), and by the ability to photoconvert a thin optical section in a three-dimensional matrix. The characteristic emission spectrum changed from red to blue, and ratiometric analysis on single cells in vitro revealed a 65-fold increase in the blue to red wavelength ratio after photoconversion. The spectral shift is preserved in vivo for hours, making Di-8-ANEPPS a useful dye for intravital cell marking and tracking applications.
authors.affiliation: Wellman Center for Photomedicine and Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114, USA.
authors.forename: Raphaël
authors.initials: R
authors.lastname: Turcotte
authors.affiliation: Wellman Center for Photomedicine and Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114, USA.
authors.forename: Juwell W
authors.initials: JW
authors.lastname: Wu
authors.affiliation: Wellman Center for Photomedicine and Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114, USA.
authors.forename: Charles P
authors.initials: CP
authors.lastname: Lin
mesh_terms: D000818:Animals; D002462:Cell Membrane; D005456:Fluorescent Dyes / Q000737:chemistry*; D000069416:Intravital Microscopy; D007834:Lasers; D008810:Mice, Inbred C57BL; D011726:Pyridinium Compounds / Q000737:chemistry
chemical_list: C089669:1-(3-sulfonatopropyl)-4-(beta-(2-(di-n-octylamino)-6-naphthyl)vinyl)pyridinium betaine; D005456:Fluorescent Dyes; D011726:Pyridinium Compounds
keywords: Photoconversion; bone marrow; cell tracking; intravital microscopy; multiphoton; two-photon fluorescence microscopy