Photochemical characteristics of cyanine dyes. Part 1.—3,3′-diethyloxadicarbocyanine iodide and 3,3′-diethylthiadicarbocyanine iodide

Dempster, D. N.; Morrow, Thomas; Rankin, R.; Thompson, G. F.

doi:10.1039/f29726801479

Cited by 179 publications

(91 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5 below). Using a triplet absorption cross section of (x T (667 nm)«4.8x 10"" 16 cm 2 [10], the mole fraction of DODCI molecules, x T =N T /N 0i transferred to the triplet state is estimated to be XT(/OL= 150 W/cm 2 ) < 0.007. This fraction is neglected in the further analysis.…”

Section: Methodsmentioning

confidence: 99%

“…The influence of intersystem crossing and triplet absorption is checked by sample excitation at A L =514 nm and absorption probing at A pr =667 nm (triplet absorption has T,-T 2 absorption peak at A«667 nm [10]). A tungsten lamp filtered with an interference filter is used as probe light.…”

Section: Methodsmentioning

confidence: 99%

“…The excitation of DODCI to the S, state leads to photoisomerization and to the accumulation of molecules in the P-isomer S 0 electronic ground state [10][11][12][13] .The groundstate P-isomer to N-isomer recovery time T P N is of the order of a few milliseconds at room temperature [ 11,12,14]. In some papers [ 2,8,15,16 ] the bleaching of the ground-state P-isomer absorption is thought to be responsible for the picosecond and femtosecond pulse generation in passively mode-locked rhodamine 6G dye lasers.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Accumulation of DODCI P isomers by laser excitation

Bäumler

Penzkofer

1990

Chemical Physics

View full text Add to dashboard Cite

The accumulation of molecules in the P-isomer ground state of DODCI in ethylene glycol is studied experimentally and theoretically. The P-isomer S 0 state is populated by S 0 -S, absorption of cw argon ion laser light or dye laser light at various wavelengths. The population is probed by the absorption of a weak He-Ne laser. The recovery to the thermal ground-state equilibrium of N and P isomers is determined by measuring the temporal probe light absorption after pump laser switch-off. A steady-state level population theory is derived and applied to determine P-isomer SQ-S, absorption cross sections and transfer efficiencies between N isomers and P isomers.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Accumulation of DODCI P isomers by laser excitation

Bäumler

Penzkofer

1990

Chemical Physics

View full text Add to dashboard Cite

show abstract

“…Cyanine dyes are known to undergo photo-induced intersystem crossing from an excited singlet state to a dark triplet state [17,18]. Photo-induced trans-cis isomerization of the dye to a non-fluorescent cis isomer is also possible [17].…”

mentioning

confidence: 99%

Short-Range Spectroscopic Ruler Based on a Single-Molecule Optical Switch

Blosser²,

2005

View full text Add to dashboard Cite

We demonstrate a novel all-optical switch consisting of two molecules: a primary fluorophore that can be switched between its fluorescent and dark states by light of different wavelengths, and a secondary chromophore that facilitates switching. The interaction between the two molecules exhibits a distance dependence much steeper than that of Förster resonance energy transfer. This enables the switch to act as a ruler with the capability to probe distances difficult to access by other spectroscopic methods, thus presenting a new tool for the study of biomolecules at the singlemolecule level.Single-molecule technologies have made a significant impact in many areas of science and engineering, ranging from electronics and photonics to molecular and cell biology. The detection of single biomolecules has transformed the way we study biological systems [1][2][3][4][5][6][7]. It is now evident that proteins, RNA and even DNA molecules are much more dynamic than previously thought, exhibiting structural dynamics essential for their function. Experiments that probe the behaviour of individual molecules in real time have proven to be ideal for characterizing these structural dynamics and their functional implications. Förster resonance energy transfer (FRET) is the most widely adopted technique for studying the conformational dynamics of individual biomolecules [6][7][8][9]. The FRET efficiency ε between a donor and an acceptor fluorophore depends on the intermolecular distance R, with ε = 1 / (1 + (R / R 0 ) 6 ). The Förster radius R 0 is typically 4 -6 nm for donor-acceptor pairs that are sufficiently bright to be detected at the single-molecule level. Therefore, single-molecule FRET is a useful probe of conformational changes on the order of several nanometers [6][7][8][9][10][11][12]. Few methods exist for the study of structural dynamics at shorter length scales. A promising technique for monitoring angstrom-scale distances, based on electron transfer, has recently been demonstrated using a flavin enzyme [13]. However, the length scale of 1 -3 nm remains difficult to access by non-invasive single-molecule techniques.In this work, we demonstrate a single-molecule optical switch which can function as a shortrange spectroscopic ruler to probe distances down to 1 nm. The molecular switch is based on a cyanine dye, Cy5, which we designate as the primary switch molecule, and a secondary chromophore, Cy3, which facilitates switching of the Cy5. For the purpose of single-molecule †To whom correspondence should be addressed. E-mail: zhuang@chemistry.harvard.edu. * These authors contributed equally to this work detection, the Cy5 and Cy3 were attached to opposite strands of a double-stranded DNA molecule and immobilized on a fused quartz surface through a streptavidin-biotin linkage (Fig. 1A). Molecules immobilized on a polyethylene glycol (PEG)-coated surface yielded similar results. Individual Cy5/DNA/Cy3 constructs were imaged in Tris buffer (pH 7.5) with an oxygen scavenging system to reduce the photobleaching rate...

show abstract

“…The organic dye DODCI (3,3'-diethyloxadicarbocyanine iodide) [1,2] is widely used as a saturable absorber in passively mode-locked pulsed dye lasers [3,4] and c.w. dye lasers [5][6][7][8].…”

Section: Introductionmentioning

confidence: 99%

Saturable absorption dynamics of DODCI

Penzkofer

Bäumler

1991

Opt Quant Electron

View full text Add to dashboard Cite

The saturable absorption dynamics of DODCI in a femtosecond dye laser is studied theoretically. The N-isomer and P-isomer photoisomerization dynamics is included. The wavelength region between 570 nm and 650 nm is considered where the N-isomer and P-isomer absorption dynamics changes from short-wavelength to longwavelength So-Si excitation. The slow saturable absorber DODCI shortens a circulating pulse in a laser oscillator down to femtosecond duration if the gain medium compensates the absorber losses. Fast local relaxation in the S 1 -state in the case of short-wavelength excitation and fast level refilling in the S^state in the case of longwavelength excitation facilitate the pulse shortening and the background signal suppression. In some papers [3, 11, 15, 16] the bleaching of the ground-state P-isomer absorption is thought to be responsible for the picosecond and femtosecond pulse generation in passively mode-locked rhodamine 6G dye lasers in the wavelength region above 600 nm. IntroductionIn this paper a detailed numerical analysis of the saturable absorption dynamics of DODCI in the wavelength region between 570 nm and 650 nm is given. The single transit of a pulse through the absorber and the repetitive passage of a pulse circulating in an oscillator are studied. The N-isomer-P-isomer photoisomerization dynamics is included [13,14]. In the long-wavelength absorption region the bleaching dynamics of the fraction of molecules interacting with the laser light is considered [17,18]. It is found that the slow saturable absorber is able to shorten nanosecond Gaussian pulses down to femtosecond pulses in multiple passages if the gain medium compensates the absorber losses. The fast relaxation of the excited Franck-Condon level in the S,-state in the case of short-wavelength excitation, and the fast spectral cross-relaxation in the S 0 -ground state in the case of

show abstract

Photochemical characteristics of cyanine dyes. Part 1.—3,3′-diethyloxadicarbocyanine iodide and 3,3′-diethylthiadicarbocyanine iodide

Cited by 179 publications

References 0 publications

Accumulation of DODCI P isomers by laser excitation

Accumulation of DODCI P isomers by laser excitation

Short-Range Spectroscopic Ruler Based on a Single-Molecule Optical Switch

Saturable absorption dynamics of DODCI

Contact Info

Product

Resources

About