Nonlinear optical phenomena due to donor–acceptor interfaces created in Langmuir–Blodgett films

Bjørnholm, Thomas; Geisler, T.; Larsen, Jan; Jørgensen, Mikkel

doi:10.1039/c39920000815

Cited by 24 publications

(13 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The purity and identity of the porphyrins were confinned by means of TLC and spectral methods. EP: NMR (CDCI,) 6 The TTP and TBP were synthesized by the standard procedure (1 8). The appropriate p-tolyl-or 3,5-di-tert-butylbenzaldehyde (1.25 mmol) and pyrrole (1.25 mmol) were dissolved in 125 mL of CH2CI2 (distilled from K,CO,) under nitrogen.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Structurally Controlled Porphyrin‐Aggregation Process in Phospholipid Membranes

Borovkov

Anikin

Wasa

et al. 1996

Photochem & Photobiology

View full text Add to dashboard Cite

Structurally controlled aggregation course for five porphyrins (etioporphyrin [EP], 5-mono-and 5,lS-di-lp-tolylletioporphyrin [TP and DTP], 5,10,15,20-tetrakislpp-tolyllporphin [TTP], and 5,10,15,2O-tetrakis[3,5-di-tert-b~tylphenyllporphin [TBP]) in dipalmitoyl-phosphatidylcholine liposomes has been monitored by fluorescence and absorption spectroscopy. While TBP shows no tendency to aggregate in liposomes, EP, TP, DTP and TTP form a porphyrin-enriched domain in membrane interior with time. The further aggregation steps within porphyrin clusters resulting in formation of stacked porphyrin aggregates have been observed for EP, TP and DTP.

show abstract

Section: Methodsmentioning

confidence: 99%

“…The purity and identity of the porphyrins were confirmed by TLC and spectral methods. TTP: 'H NMR (CDCI,) 6 Liposome preparation. The DPPC was obtained by standard acylation of sn-glycero-3-phosphorylcholine cadmium chloride complex by palmitic anhydride (19,20).…”

Section: Methodsmentioning

confidence: 99%

Structurally Controlled Porphyrin‐Aggregation Process in Phospholipid Membranes

Borovkov

Anikin

Wasa

et al. 1996

Photochem & Photobiology

View full text Add to dashboard Cite

show abstract

“…Organized chromophore assemblies are a focus for current research in areas as diverse as light harvesting (Stewart and Fox, 1996), molecular electronics (Borovkov et al, 1996;Lindsey, 1991), nonlinear optics (Bjornholm et al, 1992), and chemotherapeutics (Biolo et al, 1994). Many of these investigations employ porphyrins and the closely related phthalocyanines; these intensely colored substances, and especially the porphyrins, are relatively easy to synthesize and "tune" through judicious selection of peripheral substituents and inserted metals (Pasternack and Gibbs, 1996).…”

Section: Introductionmentioning

confidence: 99%

A Spectroscopic and Thermodynamic Study of Porphyrin/DNA Supramolecular Assemblies

Pasternack

Goldsmith

Szép

et al. 1998

Biophysical Journal

View full text Add to dashboard Cite

Assemblies of trans-bis(N-methylpyridinium-4-yl)diphenylporphine ions on the surface of calf thymus DNA have been studied using several spectroscopic techniques: absorbance, circular dichroism, and resonance light scattering. The aggregation equilibrium can be treated as a two-state system-monomer and assembly-each bound to the nucleic acid template. The aggregate absorption spectrum in the Soret region is resolved into two bands of Lorentzian line shape, while the DNA-bound monomer spectrum in this region is composed of two Gaussian bands. The Beer-Lambert law is obeyed by both porphyrin forms. The assembly is also characterized by an extremely large, bisignate induced circular dichroism (CD) profile and by enhanced resonance light scattering (RLS). Both the CD and RLS intensities depend linearly on aggregate concentration. The RLS result is consistent with a model for the aggregates as being either of a characteristic size or of a fixed distribution of sizes, independent of total porphyrin concentration or ionic strength. Above threshold values of concentration and ionic strength, the mass action expression for the equilibrium has a particularly simple form: K' = cac-1; where cac is defined as the "critical assembly concentration."offe dependence of the cac upon temperature and ionic strength (NaCl) has been investigated at a fixed DNA concentration. The value of the cac scales as the inverse square of the sodium chloride concentration and, from temperature dependence studies, the aggregation process is shown to be exothermic.

show abstract

“…The porphyrins and their derivates can find a lot of applications and are used in photodynamic therapy (PDT) of cancer, in laser technology, in light to electric energy conversion process, in optoelectronics and others [1][2][3][4][5]. Consequently the investigations of processes occurring after light absorption (radiative, non-radiative and charge separation) are needed.…”

Section: Introductionmentioning

confidence: 99%

Photovoltage generation and fluorescence of charged tetraphenylporphyrins with dopa melanin

Hanyż

Wróbel²

2003

Cryst. Res. Technol.

View full text Add to dashboard Cite

Positively charged tetra(4-N,N,N,N-trimethylanilinium) porphyrin (TAP) and negatively charged tetrakis(4-sulphonatophenyl) porphyrin (TPPS 4 ) and their mixtures with dopa melanin in polyvinyl alcohol have been investigated. On the basis of the absorption and fluorescence spectra it has been established the formation of TAP-dopa melanin complex which fluorescence is quenched whereas TPPS 4 fluorescence behaviour is only slightly changed in the presence of dopa melanin. Photovoltaic effects and photocurrent generation in a photoelectrochemical cell consisting of a layer dye solutions sandwiched between the semiconducting and gold electrodes have been investigated. The dependence of photovoltage signal on excitation wavelength (photovoltage action spectrum), kinetics of photocurrent rise and decay in the second time scale have been presented. Electric parameters of the photoelectrochemical cell (conductivity and capacitance) with porphyrin dyes, dopa melanin and their mixtures in the dark and upon illumination have been estimated. It was shown that all investigated dyes are able to generate photosignal but the values of photocurrent generated depend on the dye used in the experiment and the presence or absence of dopa melanin.

show abstract

Nonlinear optical phenomena due to donor–acceptor interfaces created in Langmuir–Blodgett films

Cited by 24 publications

References 6 publications

Structurally Controlled Porphyrin‐Aggregation Process in Phospholipid Membranes

Structurally Controlled Porphyrin‐Aggregation Process in Phospholipid Membranes

A Spectroscopic and Thermodynamic Study of Porphyrin/DNA Supramolecular Assemblies

Photovoltage generation and fluorescence of charged tetraphenylporphyrins with dopa melanin

Contact Info

Product

Resources

About