title: Photophysics of new photostable rylene derivatives: applications in single-molecule studies and membrane labelling.
abstract: Three new photostable rylene dyes for applications in single molecule studies and membrane labelling have been synthesized and their photophysical properties were characterized. These dyes differ in the number of polyethylene glycol (PEG) chains attached to the core structure which is either a perylene derivate or a terrylene derivate. One perylene and one terrylene dye is modified with two PEG chains, and another terrylene derivate has four PEG chains. The results show that the terrylene dye with four PEG chains (4-PEG-TDI) forms soluble nonfluorescing H-aggregates in water, so that the absorption bands are blue-shifted with respect to those of the fluorescing monomeric form. The presence of a surfactant such as Pluronic P123 leads to the disruption of the aggregates due to the formation of monomers in micelles and a strong increase in fluorescence. Application for labelling cell membranes can be considered for this dye since it adsorbs in a similar way as monomer to a lipid bilayer. Furthermore a single-molecule study of all three rylene dyes in polymeric films of PMMA showed excellent photostability with respect to photobleaching, far above the photostability of other common water-soluble dyes, such as Oxazine-1, Atto647N, Cy5, Alexa647 and Rhodamin6G. Especially 4-PEG-TDI seems to be a promising dye for membrane labelling with its high photostability.
authors.affiliation: Department of Chemistry and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany.
authors.forename: Melari
authors.initials: M
authors.lastname: Davies
authors.forename: Christophe
authors.initials: C
authors.lastname: Jung
authors.forename: Philipp
authors.initials: P
authors.lastname: Wallis
authors.forename: Tobias
authors.initials: T
authors.lastname: Schnitzler
authors.forename: Chen
authors.initials: C
authors.lastname: Li
authors.forename: Klaus
authors.initials: K
authors.lastname: Müllen
authors.forename: Christoph
authors.initials: C
authors.lastname: Bräuchle
mesh_terms: D000873:Anthracenes / Q000737:chemistry*; D002232:Carbocyanines / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry*; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D010078:Oxazines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D012235:Rhodamines / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D000873:Anthracenes; D002232:Carbocyanines; D005456:Fluorescent Dyes; D010078:Oxazines; D012235:Rhodamines; C085321:cyanine dye 5; C528989:terrylene; C026188:rhodamine 6G; C067297:8-aminohexylamino cAMP; D011092:Polyethylene Glycols; C025904:oxazine 1; D000242:Cyclic AMP