title: Fluorescence imaging of mitochondria in living cells using a novel fluorene derivative with a large two-photon absorption cross-section.
abstract: We have examined optical properties of a fluorene derivative with two positively charged substituents, 1,1'- diethyl-4,4'-(9,9-diethyl-2,7-fluorenediyl-2,1-ethanediyl)dipyridinium perchlorate (1), in water. The photoluminescence quantum yield of 1 was relatively high (35%) for use as a fluorescent probe in water. We also examined two-photon absorption (TPA) properties of 1 in methanol. The maximum value of the TPA cross-section (730 GM at 750 nm, 1 GM = 10(-50) cm4 s photon-1 molecule-1) was larger than that for most two-photon-excited fluorescent dyes including a classical mitochondria-selective fluorescent dye rhodamine 123. Preliminary fluorescence imaging experiments of the mitochondria in living Paramecium caudatum and HeLa cells were carried out with 1. Bright green fluorescence was observed from the mitochondria in both living cells loaded 1 without toxicity effects. These our results indicate that water-soluble fluorene derivative 1 is a promising candidate as a two-photon-excited fluorescence probe for mitochondria in living cells.
authors: Graduate School of Science and Engineering, Yamaguchi University, 1677-1 Yoshida, Yamaguchi, 753- 8512, Japan. stani@yamaguchi-u.ac.jp
authors: Seiji
authors: S
authors: Tani
authors: Kenta
authors: K
authors: Nakagawa
authors: Takuya
authors: T
authors: Honda
authors: Hiromasa
authors: H
authors: Saito
authors: Yasutaka
authors: Y
authors: Suzuki
authors: Jun
authors: J
authors: Kawamata
authors: Makiyo
authors: M
authors: Uchida
authors: Akira
authors: A
authors: Sasaki
authors: Masataka
authors: M
authors: Kinjo
mesh_terms: D000042:Absorption; D005449:Fluorenes / Q000737:chemistry / Q000494:pharmacology*; D005456:Fluorescent Dyes / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000378:metabolism*; D048488:Paramecium caudatum / Q000378:metabolism*; D017785:Photons
chemical_list: D005449:Fluorenes; D005456:Fluorescent Dyes; D007211:Indoles; C007293:DAPI