Two-photon absorption properties of hexa-substituted benzene derivatives. Comparison between dipolar and octupolar molecules.

Hexa-substituted benzene derivatives show larger two-photon cross sections than the corresponding dipolar counterparts and the largest values of delta(max) = 2000 GM and delta(max)/MW = 2.25 GM g(-1) have been obtained with a compound having C[triple bond]C and C=C bonds in the conjugation bridge.

Two-photon fluorescent turn-on probe for lipid rafts in live cell and tissue.

We report a new two-photon fluorescence turn-on probe 6-[(E)-3-oxo-1-dodecenyl]-2-[N-methyl-N-(carboxymethyl)amino]naphthalene (CL2) that is designed specifically for visualizing lipid rafts in living cells and tissues. This probe emits much brighter two-photon excited fluorescence in lipid rafts than in non-raft domains and allows direct visualization of the lipid rafts in the live cells and pyramidal neuron layer of the CA1 region at a depth of 100-250 mum in live tissues using two-photon microscopy.

Two-photon absorption properties of 9,10-disubstituted 2,6-bis(p-dihexylaminostyryl)anthracene derivatives. Effect of 9,10-substituents.

A series of 2,6-bis(p-dihexylaminostyryl)anthracence derivatives having phenyl, styryl, and phenylethynyl groups at 9,10-positions (1-4) have been synthesized and their two-photon cross-sections were determined. Overall, the wavelengths of the longest wavelength absorption band and emission spectra increase with increase in the conjugation length and the electron withdrawing ability of the 9,10-substituents. All compounds show two-photon cross sections in the range of 740-3940 GM at 780-960 nm, which increase significantly by the donor and acceptor groups at 9,10-positions.

Magnesium ion selective two-photon fluorescent probe based on a benzo[h]chromene derivative for in vivo imaging.

A novel, two-photon probe for the detection of free Mg2+ ions in living cells and live tissues has been developed. The probe can be excited by 880 nm laser photons, emits strong two-photon excited fluorescence in response to Mg2+ ions, can be easily loaded into the cell and tissue, shows high photostability, and can measure the Mg2+ ion concentration without interference by Ca2+ ions in living cells. The intracellular dissociation constant (Kdi) for Mg2+ determined by the two-photon process is 2.