Solid meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS(4))-chitosan supramolecular complexes were prepared by addition of porphyrin to an aqueous solution of chitosan at pH values. The precipitates obtained were assigned as 1 (pH 6.8) and 2 (pH 2.5) and characterized by spectroscopic, thermal, and microscopic methods. Spectroscopic investigation confirmed the presence of TPPS(4) and chitosan in both products and that the porphyrin is highly self-associated. H-type (stacked) of TPPS(4) aggregation was proposed for 1 and J-type (tilted) for 2. Thermal analysis revealed different pyrolysis routes of the complexes depending on their structural diversity. Light microscopic analysis indicated fibrous and lamellar microstructures, respectively, for 1 and 2. SEM and AFM analysis showed that both complexes consist of compact nanostructures; their size and interconnection is different for 1 and 2. Based on structural inferences, self-assembling hierarchy models were proposed for both of the TPPS(4)-chitosan supramolecular complexes.

• MeSH
• blízká infračervená spektroskopie MeSH
• chitosan chemie   MeSH
• koncentrace vodíkových iontů MeSH
• magnetická rezonanční spektroskopie MeSH
• mikroskopie atomárních sil MeSH
• molekulární struktura MeSH
• nanostruktury chemie   MeSH
• porfyriny chemie   MeSH
• povrchové vlastnosti MeSH
• teplota MeSH
• velikost částic MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chitosan MeSH
• meso-tetrakis(4-sulfonatophenyl)porphyrin MeSH Prohlížeč
• porfyriny MeSH

The infrared (IR) and vibrational circular dichroism (VCD) spectra of guanosine-5'-hydrazide ( G-1), a powerful hydrogelator, have been measured and analyzed on the basis of ab initio modeling. B3LYP/6-31G** DFT calculations predict that G-1, forming a clear solution in deuterated DMSO, is present in monomeric form in this solvent, whereas strong gelation in a phosphate buffer is due to the formation of a guanine-quartet structure, ( G-1)4, in which the four G-1 are linked by hydrogen-bonded guanine moieties and stabilized by an alkali metal cation. The B3LYP/6-31G** IR and VCD spectra of the nearly planar G-quartet, whose structure is slightly distorted from the C4h symmetry, in which the G-bases interact via four Hoogsteen-type hydrogen bonds and a sodium cation is positioned in the middle of the G-quartet, are in very good agreement with the experimental spectra, indicating that this structure is the predominant structure in the gel state. The geometric parameters are discussed. This study is the first to use IR and VCD spectroscopies coupled with DFT calculations to elucidate the structure of a supramolecular species in a gel state and shows the VCD spectroscopy as a powerful method for investigating the structure of complex supramolecular self-assemblies where the use of other structural methods is limited.

• MeSH
• cirkulární dichroismus MeSH
• dimerizace MeSH
• gely chemie   MeSH
• guanin chemie   MeSH
• molekulární modely MeSH
• molekulární struktura MeSH
• sacharidy chemie   MeSH
• spektrofotometrie infračervená MeSH
• vibrace * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• gely MeSH
• guanin MeSH
• sacharidy MeSH

Interaction of meso-tetrakis(4-sulphonatophenyl)porphine (TPPS4) with chitosan (Mr approximately 400 kDa, N-acetyls approximately 20 mol.%) was studied in aqueous solutions. UV-vis absorption and circular dichroism (CD) spectroscopic titration of 10 micromol l-1 TPPS4 with chitosan demonstrated that an addition of the polysaccharide at appropriate concentrations and pH values induce and support self-aggregation of the macrocycles. The mode of aggregation was strongly dependent on pH: stacking (H-type) aggregates predominated at weak acidic conditions (pH 4.8-6.8) and tilted (J-type) aggregates at pH 2.5. At the intermediate pH value (3.6) both types of TPPS4 aggregates were detected. High amount of chitosan (>0.05 mmol l-1 of GlcN) disrupts H-aggregates forming monomeric porphyrin-chitosan complexes (pH 3.6-6.8), while J-aggregates (pH 2.5) are stable even at very high chitosan concentrations. CD titration experiments confirmed the formation of optically active species of TPPS4 in the presence of chitosan. The complex nature of CD bands assigned to both types of porphyrin aggregates indicated the occurrence of several chiral macrocyclic species dependently on pH value and chitosan concentration.

• MeSH
• chitosan chemie   MeSH
• cirkulární dichroismus MeSH
• koncentrace vodíkových iontů MeSH
• molekulární struktura MeSH
• porfyriny chemie   MeSH
• spektrofotometrie ultrafialová MeSH
• stereoizomerie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chitosan MeSH
• porfyriny MeSH
• porphine MeSH Prohlížeč

The self-assembly of guanosine-5'-hydrazide G-1 in D(2)O, in the presence and absence of sodium cations, has been investigated by chiroptical techniques: electronic (ECD) and the newly introduced vibrational (VCD) circular dichroism spectroscopy. Using a combination of ECD and VCD with other methods such as IR, electron microscopy, and electrospray ionization mass spectrometry (ESI-MS) it was found that G-1 produces long-range chiral aggregates consisting of G-quartets, (G-1)(4), subsequently stacked into columns, [(G-1)(4)](n), induced by binding of metal cations between the (G-1)(4) species. This process, accompanied by gelation of the sample, is highly efficient in the presence of an excess of sodium cations, leading to aggregates with strong quartet-quartet interaction. Thermally induced conformational changes and conformational stability of guanosine-5'-hydrazide assemblies were studied by chiroptical techniques and the melting temperature of the hydrogels formed was obtained. The temperature-dependent experiments indicate that the long-range supramolecular aggregates are dissociated by increasing temperature into less ordered species, monomers, or other intermediates in equilibrium, as indicated by MS experiments.

• MeSH
• biomedicínský výzkum metody   MeSH
• cirkulární dichroismus MeSH
• elektronika MeSH
• elektronová mikroskopie MeSH
• guanosin chemie   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• hydrogely chemie   MeSH
• molekulární konformace MeSH
• spektrofotometrie infračervená MeSH
• termodynamika MeSH
• vazebná místa MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• guanosin MeSH
• hydrogely MeSH

Tetrabrucin-porphyrin as a sensor for ATP was designed and tested; selectivity for ATP was proved in the presence of ADP and AMP.

• MeSH
• adenosintrifosfát analýza   MeSH
• alkaloidy chemická syntéza   chemie   MeSH
• porfyriny chemická syntéza   chemie   MeSH
• senzitivita a specificita MeSH
• spektrální analýza MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adenosintrifosfát MeSH
• alkaloidy MeSH
• porfyriny MeSH

The interactions of poly-L-glutamic acid and a cationic porphyrin derivative in aqueous solutions were studied by the combination of vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) spectroscopies. It was found that non-covalent interactions between both agents influence the structure of the polymeric matrix and the guest porphyrins and vice versa, but the physico-chemical properties of the solutions, especially the pH and the relative permittivity of the solvent, play a key role in the structure of the polypeptide part of the formed complexes. It was shown that the interaction with porphyrins prevents the precipitation of poly-L-glutamic acid in aqueous solution at acidic pH. In special conditions, the porphyrins attached to the polypeptide probably possess face-to-face interaction as demonstrated by the enhancement of the characteristic ECD signal and the appearance of sidebands on its short and long wavelength sides.

• MeSH
• cirkulární dichroismus MeSH
• kyselina polyglutamová chemie   MeSH
• molekulární struktura MeSH
• porfyriny chemie   MeSH
• roztoky MeSH
• spektrofotometrie ultrafialová MeSH
• voda chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyselina polyglutamová MeSH
• porfyriny MeSH
• roztoky MeSH
• voda MeSH

The phenolic compounds p-hydroxyacetophenone and catechin have been extracted from Norway spruce needles with pure methanol, 80 and 50% (v/v) aqueous methanol, pure acetonitrile, 80% (v/v) aqueous acetonitrile, and pure water. Extraction efficiency of the individual solvents was compared. Although 80% aqueous methanol is the solvent most frequently used for extraction of soluble phenolic compounds from needles, it was found that pure methanol is a more suitable extraction solvent. Surprisingly, a two-step procedure based on the extraction of crushed needles with water then re-extraction with methanol proved a good alternative to direct extraction with methanol. Extraction of uncrushed spruce needles might indicate that relatively more p-hydroxyacetophenone than catechin was located in the surface layer of the needle.

• MeSH
• acetofenony analýza   MeSH
• acetonitrily chemie   MeSH
• katechin analýza   MeSH
• listy rostlin chemie   MeSH
• methanol chemie   MeSH
• rozpouštědla chemie   MeSH
• voda chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Geografické názvy
• Norsko MeSH
• Názvy látek
• 4-hydroxyacetophenone MeSH Prohlížeč
• acetofenony MeSH
• acetonitrile MeSH Prohlížeč
• acetonitrily MeSH
• katechin MeSH
• methanol MeSH
• rozpouštědla MeSH
• voda MeSH

Solid complexes of D-galacturonic acid (GalA) with cobalt(II), copper(II), nickel(II) and oxovanadium(IV) (1-4) were prepared and characterised. The metal-to-ligand molar ratio was 1:2 for complexes 1-3 and 1:1 for complex 4. The alpha- and beta-anomers of GalA were detected in all the complexes in solid state and in solutions. An addition of small amounts of the paramagnetic complexes to the D2O solution of pure ligand led to NMR line broadening of some 1H and 13C nuclei. This broadening was sensitive to the anomeric state of GalA in the case of complexes 1 and 4. NMR and vibrational spectroscopic data indicate the formation of carboxylate complexes of all the cations, while noncarboxylic oxygens are also involved into the metal bonding in some cases. VCD spectra of complexes 1-4 in D2O and Me2SO-d6 solutions confirm that GalA carboxylic group may participate in the formation of optically active species around the metal cation. Possible ways of GalA coordination by metal cations of this study were proposed and discussed.

• MeSH
• kationty dvojmocné chemie   MeSH
• kyseliny hexuronové chemie   MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární struktura MeSH
• roztoky MeSH
• těžké kovy chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• galacturonic acid MeSH Prohlížeč
• kationty dvojmocné MeSH
• kyseliny hexuronové MeSH
• roztoky MeSH
• těžké kovy MeSH

Biolocalisation and photochemical properties of novel macrocyclic photosensitisers, guanidiniocarbonyl-substituted tetraphenylporphyrin (1) and sugar-substituted sapphyrin (2) were investigated by spectroscopic methods. Both photosensitisers absorb in far visible region and showed good tumour localisation. Photosensitiser 2 demonstrated significantly larger absolute and relative to normal tissue (T/N) amount in tumour (330 microg g(-1) wet tissue, T/N=19.0) than photosensitiser 1 did (13 microg g(-1) wet tissue, T/N=2.1). According to iodometric and uric acid assays, compound 1 produced large amount of 1O2 (phidelta=0.60-0.68), while compound 2 showed non-significant 1O2 production (phidelta=0.04). The electronic spectroscopic study confirms that only photosensitiser 1 is able to mediate photooxidation of model compounds (BSA, poly(Trp), Tyr, Trp, and GMP) after light irradiation. Pour photochemical activity of compound 2 was explained by its self-aggregation. Raman spectroscopic study indicated that monomerised photosensitiser 2 effectively damaged BSA and calf thymus DNA after light excitation at the conditions of high excess of these macromolecules.

• MeSH
• absorpce MeSH
• DNA chemie   metabolismus   účinky záření   MeSH
• fotochemie MeSH
• fotosenzibilizující látky aplikace a dávkování   chemie   farmakokinetika   MeSH
• guanin * chemie   MeSH
• kyslík metabolismus   MeSH
• molekulární struktura MeSH
• myši MeSH
• nádory metabolismus   patologie   MeSH
• porfyriny aplikace a dávkování   chemie   farmakokinetika   MeSH
• Ramanova spektroskopie MeSH
• roztoky chemie   MeSH
• sacharidy chemie   MeSH
• sérový albumin hovězí chemie   metabolismus   MeSH
• spektrální analýza MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• fotosenzibilizující látky MeSH
• guanin * MeSH
• kyslík MeSH
• porfyriny MeSH
• roztoky MeSH
• sacharidy MeSH
• sapphyrin MeSH Prohlížeč
• sérový albumin hovězí MeSH
• tetraphenylporphyrin MeSH Prohlížeč

The use of near-infrared (NIR)-excited Fourier-transform (FT) Raman spectroscopy as a technique for evaluating the extent of photosensitizer localization in tumor (human pancreatic adenocarcinomas)-bearing mice has been tested using lutetium(III) texaphyrin analogue Lu-T2B2Tex. The complex was injected subcutaneously in the form of three injections given during the course of 3 days. The kinetics of biodistribution were then followed over a time scale of 1-6 days. The NIR-FT-Raman spectra of tissue samples obtained from the xenographic tumor, muscle, heart, brain, liver, spleen, kidney and blood were recorded and used to identify the presence of Lu-T2B2Tex in these tissues. Five Raman sensitizer markers were used to estimate the relative content of Lu-T2B2Tex in tumor at various postinjection times. UV-Visible (Vis) absorption spectroscopic detection of this sensitizer in tissue extracts was applied as a conventional method. Both spectroscopic methods were in good agreement with each other and confirm that Lu-T2B2Tex localizes well in tumor tissue. Maximal drug content was observed 3 days after the final injection. This time delay seems to be optimal for tumor irradiation in photodynamic therapy.

• MeSH
• adenokarcinom metabolismus   MeSH
• blízká infračervená spektroskopie přístrojové vybavení   metody   MeSH
• dusičnany farmakokinetika   MeSH
• fotosenzibilizující látky farmakokinetika   MeSH
• inbrední kmeny myší MeSH
• lidé MeSH
• metaloporfyriny farmakokinetika   MeSH
• modely u zvířat MeSH
• molekulární struktura MeSH
• myši nahé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory slinivky břišní MeSH
• Ramanova spektroskopie přístrojové vybavení   metody   MeSH
• spektrofotometrie ultrafialová MeSH
• spektroskopie infračervená s Fourierovou transformací přístrojové vybavení   metody   MeSH
• tkáňová distribuce MeSH
• transplantace nádorů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, P.H.S. MeSH
• Názvy látek
• dusičnany MeSH
• fotosenzibilizující látky MeSH
• metaloporfyriny MeSH
• motexafin lutetium MeSH Prohlížeč