UV–visible, fluorescence and EPR properties of porphyrins and metalloporphyrins

Zheng, Weitao; Shan, Ning; Yu, Lianxiang; Wang, Xingqiao

doi:10.1016/j.dyepig.2007.04.007

Cited by 194 publications

(110 citation statements)

References 21 publications

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“…The UV-Vis absorption spectrum of the free ligand PR-SH exhibited the Soret band at  = 422 nm and the four Q bands between 500 and 700 nm characteristic of metal free porphyrin derivatives. 27 The characteristic Soret band was also observed in the UV-Vis extinction spectra of the synthesised nanoparticles, PRAuNP and PR-AuNP-PEG, albeit slightly shifted from that of the free ligand, at ca. …”

Section: Uv-vis Extinction Spectroscopymentioning

confidence: 83%

“…650 and 712 nm that are characteristic of porphyrin derivatives. 27 The two characteristic bands were also observed for the PR-AuNP-PEG (monophasic) and for PR-AuNP; however, they were not present in the fluorescence emission spectrum of the PR-AuNP-PEG (biphasic) possibly due to the low concentration of PR-SH on the surface of these nanoparticles. The fluorescence excitation spectra of the free ligand PR-SH and of the functionalised nanoparticles were also obtained ( Figure S7).…”

Section: Fluorescence Spectroscopymentioning

confidence: 91%

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Water soluble, multifunctional antibody-porphyrin gold nanoparticles for targeted photodynamic therapy

Penon

Marín

Russell

et al. 2017

Journal of Colloid and Interface Science

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Photodynamic therapy (PDT) is a treatment of cancer by which tumour cells are destroyed using reactive oxygen species produced by photosensitisers following activation with visible or near infrared light. Successful PDT depends on the solubility and the targeting ability of the photosensitisers. In this work, the synthesis of a porphyrin-based water soluble nanoparticle conjugate containing a targeting agent that recognises the erbB2 receptor overexpressed on the surface of particular cancer cells is reported. The nanoparticle conjugates were synthesised following two different protocols, viz. a biphasic and a monophasic method, with the aim to determine which method yielded the optimal nanosystem for potential PDT applications. The nanoparticles were characterised using UV-Vis absorption and fluorescence spectroscopies together with transmission electron microscopy and zeta potential measurements; and their ability to produce singlet oxygen following irradiation was investigated following the decay in absorption of a singlet oxygen probe. The nanoparticles synthesised using the monophasic method were shown to produce the highest amount of singlet oxygen and were further functionalised with anti-erbB2 antibody to target the erbB2 receptors expressed on the surface of SK-BR-3 human breast cancer cells. The water soluble, antibody-porphyrin nanoparticle conjugates were shown to elicit targeted PDT of the breast cancer cells.

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Section: Uv-vis Extinction Spectroscopymentioning

confidence: 83%

Section: Fluorescence Spectroscopymentioning

confidence: 91%

Water soluble, multifunctional antibody-porphyrin gold nanoparticles for targeted photodynamic therapy

Penon

Marín

Russell

et al. 2017

Journal of Colloid and Interface Science

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“…This spectral behavior was similar to other meso-porphyrins and indicates that these compounds can be used in optoelectronic systems working in the red spectral region, for example as catalyst, solar cells, OLEDs (organic light-emitting diode) and photodynamic therapy. 38,39 The fluorescence emission was attributed to the transition from the excited singlet state S 1 /S 2 to the ground state S 0 (S 2 → S 0 , S 1 → S 0 ). The spectra of the complexes 4b-d showed a very weak fluorescence band, and when 4b is excited at 421 nm, this band appeared at 651 nm with intensity about 2 × 10 3 a.u.…”

Section: Electronic Absorption and Luminescence Spectramentioning

confidence: 99%

Synthesis, Characterization and Dielectric Properties of New 5-(4-Hydroxyphenyl)-10,15,20-tri-4-[2-(3-pentadecylphenoxy)ethoxy]phenyl porphyrin and Their Ni, Co and Cu Complexes

Mota¹,

Júnior²,

Ribeiro³

et al. 2016

J. Braz. Chem. Soc.

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New asymmetric cardanol-based porphyrins, free-base and coordinated with Ni, Co and Cu, were synthesized and completely characterized as A3B type. Such porphyrins were obtained aiming improved solubility in polar solvents due insertion of an −OH phenolic group. Their thermal and dielectric properties were also evaluated. Changes in the synthetic route reduced the reaction time and improved the yields of the aldehyde precursor obtainment. Electronic absorption spectra of the new porphyrins in CH 2 Cl 2 , EtOH and acetone, indicated a decrease in the ε (molar absorptivity) values with increasing solvent polarity, except for the nickel complex which, in acetone, showed a slight increase of 2% in the ε value. The dielectric measurements showed that the conductivity (σ) and the loss tangent (tan δ) increased with frequency, but the permittivity (ε') decreased. The results showed that the coordination of the porphyrin promoted a significant change in thermal and dielectric properties, specially for to the Ni-complex compound, which presented the best dielectric properties with interesting values of permittivity and loss tangent at 100 MHz (19.46 and 0.011 a.u., respectively). Keywords: asymmetric porphyrins, cardanol, dielectric properties IntroductionPorphyrins are relatively planar aromatic system consisting of four pyrrole type rings joined by four methynic carbons. They have attracted scientists from many areas due to their biological importance, their fascinating physical, chemical, and spectroscopic properties.1 These compounds have a high electron density due to its 18 π-electrons delocalized on the macrocyclic ring, which are responsible for their spectroscopic characteristics. 2Porphyrin and its derivatives play multiple roles in nature, such as energy transfer and light absorption in a wide range of the electromagnetic spectrum. Such features are of great interest to the industry of optoelectronic components, such as solar cells, due to its ability to act as photosensitizers when irradiated under visible light.3 Thus, this is certainly one of the most promising areas of application for these compounds. The structural modeling and synthesis of new porphyrins has grown exponentially in order to control their electronic and thermal properties. 4 The addition of substituents at the meso positions and metal ions in the center of porphyrins can improve the electrical and magnetic properties, protecting against auto-oxidation and reducing the formation of dimers. However, these structural modifications can promote, in some cases, a significant decrease in their planarity. 5A simple way to obtain porphyrins is the acid catalyzed condensation reaction of pyrrole with specific aldehyde, followed by oxidation of the porphyrinogen. This procedure, originally developed by Rothemund,6 has been refined by [7][8][9] due to the addition of metal salts to the reaction. Despite the modest yields, the relative simplicity of this method has become suited for preparation of large amounts of tetraarylporphyrins. Higher yields an...

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“…La disminución del número de bandas Q es típico de las metaloporfirinas. Cuando el ión metálico se coordina con los átomos de nitrógeno del macrociclo, la simetría de la molécula se incrementa y el número de bandas Q decrece [14]. La metalación de las porfirinas produce desplazamiento de la bandas Soret y Q por la interacción del metal con la nube electrónica π de los macrociclos.…”

Section: Espectrofotometríaunclassified

“…La metalación de las porfirinas produce desplazamiento de la bandas Soret y Q por la interacción del metal con la nube electrónica π de los macrociclos. En el espectro de la TCPPCu se observa un desplazamiento de las bandas de absorción hacia el azul, posiblemente debido a la desestabilización de la nube electrónica π del ligando inducida por el metal e incremento de la energía de transición [14].…”

Section: Espectrofotometríaunclassified

Distribución del tamaño de partícula por dispersión dinámica de luz de la tetracarboxifenilporfirina de cobre (II) anclada al dióxido de titanio

Díaz‐Uribe

Vallejo

Puello-Polo

2014

Iteckne

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UV–visible, fluorescence and EPR properties of porphyrins and metalloporphyrins

Cited by 194 publications

References 21 publications

Water soluble, multifunctional antibody-porphyrin gold nanoparticles for targeted photodynamic therapy

Water soluble, multifunctional antibody-porphyrin gold nanoparticles for targeted photodynamic therapy

Synthesis, Characterization and Dielectric Properties of New 5-(4-Hydroxyphenyl)-10,15,20-tri-4-[2-(3-pentadecylphenoxy)ethoxy]phenyl porphyrin and Their Ni, Co and Cu Complexes

Distribución del tamaño de partícula por dispersión dinámica de luz de la tetracarboxifenilporfirina de cobre (II) anclada al dióxido de titanio

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