title: Acetylene-substituted two-photon absorbing molecules with rigid elongated pi-conjugation: synthesis, spectroscopic properties and two-photon fluorescence cell imaging applications.
abstract: Two asymmetrical molecules with substituted acetylene as central rigid elongated conjugation are reported as potential chromophores for two-photon microscopic imaging. These molecules consist of a typical D-pi-A structure, have different donors (D), the same pi-conjugated center (pi) and the same acceptor (A). Structural characterization and spectroscopic properties, including single-photon (linear) absorption, quantum yields, single-photon fluorescence, and two-photon absorption spectra, were studied in solvents with different polarity. These acetylene-substituted molecules were found to have high two-photon absorption cross-sections (for example, 690 GM for molecule 1 in toluene), which were determined by a two-photon induced fluorescence method using a femtosecond Ti: sapphire laser as excitation source. Single- and two-photon cellular imaging experiments demonstrate that the substituted acetylene derivatives could be one kind of promising two-photon fluorescence probes for cellular imaging.
authors.affiliation: Key Laboratory of Biomedical Photonics of Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Hai-Li
authors.initials: HL
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Zhen-Li
authors.initials: ZL
authors.lastname: Huang
authors.forename: Yuan-Di
authors.initials: YD
authors.lastname: Zhao
authors.forename: Qing-Ming
authors.initials: QM
authors.lastname: Luo
mesh_terms: D000480:Alkynes / Q000138:chemical synthesis / Q000737:chemistry*; D002460:Cell Line; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D006801:Humans; D010777:Photochemistry; D017785:Photons; D013050:Spectrometry, Fluorescence; D013194:Staining and Labeling
chemical_list: D000480:Alkynes; D005456:Fluorescent Dyes