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Surface-enhanced resonance Raman scattering of Zn(II) porphyrins in systems with aggregated and non-aggregated Ag nanoparticles
Spáčil, Dušan ; Vlčková, Blanka (advisor) ; Procházka, Marek (referee)
In this diploma thesis, SERRS(Surface - enhanced resonance Raman Scattering) and SERS (Surface - enhanced Raman Scattering), surface of plasmon extinction spectra and TEM images of systems with tetracationic zinc porphyrin ZnTMPyP and silver nanoparticles (Ag NPs) were studied and interpreted. The systems with isolated nanoparticles and the systems with compact aggregates were investigated. The systems with isolated nanoparticles were prepared by addition of ZnTMPyP to hydrosol of Ag NPs. NaCl was added to this system and so compact aggregates were prepared. SERRS and SERS spectra of ZnTMPyP were studied at excitation wavelengths λexc= 441.6 nm a 532 nm. Firstly, stationary systems and secondly dynamic development of hydrosol Ag NPs → Ag NPs/ ZnTMPyP → Ag NPs/ ZnTMPyP/ NaCl systems for 680 s was investigated. Time evolution of SERRS and SERS spectra were analyzed by factor analysis (FA) and time evolution of spectra extinction plasmon were measured. FA showed a strong increase of the signal of ZnTMPyP after the addition of NaCl, i.e. after conversion of isolated nanoparticles to compact aggregates. In these systems with high concentration of ZnTMPyP the increase of signal was succeeded by its decreased. With help of FA the limit of SERRS spectral detection (λexc= 441,6 nm) and limit of SERS spectral...
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Molecular mechanisms of apoptosis induced by photodynamic activation in cancer cells
Moserová, Irena ; Králová, Jarmila (advisor) ; Kuželová, Kateřina (referee) ; Kovář, Jan (referee)
Photodynamic therapy (PDT) is a treatment modality for cancer. It combines selective accumulation of chemical compounds, called photosensitizers (PS), with light to irreversibly damage cancer cells via oxidative stress. The main goal of this thesis was to study photosensitizers represented by a unique group of newly synthesized porphyrin derivatives with glycol chain substitution. Glycol-functionalized porphyrins containing one to four low molecular weight glycol chains that are linked via ether bonds to the meta-phenyl positions of meso-tetraphenylporphyrin (mTPP(EG)1-4) were compared with fluorinated (pTPPF(EG)4) and nonfluorinated (TPP(EG)4) derivatives having glycol chains in para-phenyl positions. The cellular uptake and photodynamic activity was significantly dependent on terminal groups of the glycol substituent. Hydroxy glycol porphyrins, in contrast with methoxy glycol porphyrins, exhibited efficient intracellular transport and high induction of apoptosis in tumor cell lines in vitro. After initial testing effective prototype hydroxy ethylene glycol derivatives were selected and analyzed in detail. Para derivatives pTPP(EG)4 and pTPPF(EG)4 accumulated mainly in lysosomes whereas meta derivatives mTPP(EG)1-4 in the endoplasmic reticulum (ER). Position of ethylene glycol chain on the...
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Production of singlet oxygen by metal-organic frameworks
Ondrušová, Soňa ; Lang, Kamil (advisor) ; Kubíček, Vojtěch (referee)
In the presented thesis, metal-organic framework (MOF) PCN-222 was post-synthetically modified with diphenylphosphinic acid. The parent PCN-222 and modified MOFs were characterized by powder X-ray diffractions and nitrogen adsorption isotherms. The presence of bound diphenylphosphinic acid in the modified MOFs was documented by inductively coupled plasma optical emission spectrometry, infrared spectroscopy, and 13 C and 31 P solid- state NMR. The modified MOFs have greater water-drying stability and up to four times higher singlet oxygen productivity under visible light irradiation than the parent PCN-222. Keywords: metal-organic framework, porphyrin, post-synthetic modifications, diphenylphosphinic acid, singlet oxygen, stability
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Temperature-sensitive functional molecules
Spasovová, Monika ; Hanyková, Lenka (advisor) ; Starovoytova, Larisa (referee)
The object of our study is a phase separation of porphyrin derivative PNIPAm-TPP. This molecule combines the properties of temperature-responsive polymers with those of well- defined small organic molecules. It is one of the few small organic molecule which shows temperature responsive behavior. We studied its phase separation using high resolution NMR spectroscopy and optical microscope. We applied Flory-Huggins theory to experimental data gained from VT (variable temperature) experiments and we obtained a phase diagram with spinodal and binodal curve. We also obtained LCST (lower critical solution temperature) of the solution and its critical concentration.
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Studium teplotně citlivých porfyrinů a jejich supramolekulárních komplexů
Hrubovský, Martin ; Kouřilová, Hana (advisor) ; Srb, Pavel (referee)
Study of thermoresponsive porphyrins and their supramolecular complexes Abstract: We studied the water-soluble artificial compound meso-tetrakis{3,4,5-tris[2-(2-(2- methoxyethoxy)ethoxy)ethoxy]phenyl}porphyrin prepared at NIMS, Japan, using the high-resolution NMR spectroscopy experimental method. We observed its LCST-type phase separation and applied the Flory-Huggins theory of polymer solutions in order to find its phase diagram (binodal and spinodal curves of the phase separation) and we also obtained molar enthalpies, entropies and critical temperatures of its phase separation; from the Flory-Huggins theory we discovered that its molecules form dimers in aqueous solutions. We also studied its host-guest interactions with the S-camphorsulfonic acid; we learned that the porphyrin binds cations and the porphyrin dimers break down when dissolved cations are available for complexation. We observed no phase separation in chloroform. We obtained no proof of the existence of molecular stacks larger than dimers. 1
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Interakce liposomů s porfyriny studována pomocí Ramanovy spektroskopie kapkově nanášených povlaků
Vaculčiaková, Lenka ; Kočišová, Eva (advisor) ; Holoubek, Aleš (referee)
Water-soluble cationic porphyrins have been studied in relation to antisense therapy and they have been successfully used to enhance the delivery of oligonu- cleotides to cells. The main focus of this study was to characterize the mech- anism of interaction of liposomes as model membranes, and porphyrins. We applied the drop coating deposition Raman spectroscopy (DCDR) to study com- plexes of liposomes and porphyrins. DCDR allowed us to measure complexes of low concentration as it uses the 'coffee ring' effect to concentrate the sample at the edge of a drop. We studied four different complexes combined of lipids: 1, 2−dipalmitoyl−sn−glycero−3−phosphocholine, 1, 2−dioleoyl−sn−glycero− 3 − phospho − (1 − rac − glycerol) and metalloporphyrins: copper 5, 10, 15, 20 − tetrakis(1 − methyl − 4 − pyridyl)porphyrin, copper 5, 10, 15, 20 − tetrakis(4 − sulfonatophenyl)porphyrin. We have found that the way these two components interact strongly depends on a specific lipid and porphyrin used. We observed partial incorporation of porphyrins into the liposome bilayer, their localisation to the surface of the liposome or the change of the conformation and ordering of lipid molecules. Moreover, we have found that the distribution of porphyrins in the dried drop is randomly non-homogenous. 61
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Spektroskopické a teoretické studium supramolekulárních komplexů symetrických porfyrinů s chirálními guesty
Březina, Václav ; Hanyková, Lenka (advisor) ; Šoltésová, Mária (referee)
Certain types of porphyrins can be used as achiral agent for determination of enantiomeric excess (ee) of chiral molecules. Particular organic chiral molecule (guest) and porphyrin (host) form host-guest complex while inducing nonequiv- alency of particular proton resonances in symmetrical host. It causes splitting of NMR signals linearly dependent on ee of guest. In this work we investigated com- plexation of di-brombenzylated oxoporphyrin with chiral camphorsulfonic acid. NMR titration revealed that they form complex with 1:1 stoichiometry with as- sociation constant K ≈ 5 × 104 l/mol. We confirmed linear dependence of split- ting of host β-protons on ee of guest. Low temperature measurements revealed two conformations of host-guest complex with population around 0.7:0.3 (at −60 ◦ C). DFT quantum mechanical computations at BLYP/3-21G* level revealed also two conformations with population 0.79:0.21. NMR shifts were computed on this geometries with method GIAO/PBE1PBE/6-31G(2df,2pd) and compared to experimental values. 1
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Porphyrine conjugates for MRI
Dušek, Pavel ; Vojtíšek, Pavel (advisor) ; Kotková, Zuzana (referee)
The theoretical part of this bachelor's thesis focuses on clinical applications of MRI methods. It also presents a list of gadolinium-based contrast agents used in clini- cal practice. A new conjugate of 1,4,7,10-tetraazacyclododecane-4,7,10-triacetate-1- {methyl-[(4-aminophenyl)methyl]phosphinic} acid and 5,10,15,20-tetrakis(4-amino- phenyl)porphyrin potentially active as a contrast agent is designed on the basis of this review. Due to unique properties of porphyrin unit, this compound may act as a bimodal contrast agent or contrast agent for functional imaging. The target compound and its ytterbium-complex were synthesized and partially characterized.
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Molecular mechanisms of apoptosis induced by photodynamic activation in cancer cells
Moserová, Irena ; Králová, Jarmila (advisor) ; Kuželová, Kateřina (referee) ; Kovář, Jan (referee)
Photodynamic therapy (PDT) is a treatment modality for cancer. It combines selective accumulation of chemical compounds, called photosensitizers (PS), with light to irreversibly damage cancer cells via oxidative stress. The main goal of this thesis was to study photosensitizers represented by a unique group of newly synthesized porphyrin derivatives with glycol chain substitution. Glycol-functionalized porphyrins containing one to four low molecular weight glycol chains that are linked via ether bonds to the meta-phenyl positions of meso-tetraphenylporphyrin (mTPP(EG)1-4) were compared with fluorinated (pTPPF(EG)4) and nonfluorinated (TPP(EG)4) derivatives having glycol chains in para-phenyl positions. The cellular uptake and photodynamic activity was significantly dependent on terminal groups of the glycol substituent. Hydroxy glycol porphyrins, in contrast with methoxy glycol porphyrins, exhibited efficient intracellular transport and high induction of apoptosis in tumor cell lines in vitro. After initial testing effective prototype hydroxy ethylene glycol derivatives were selected and analyzed in detail. Para derivatives pTPP(EG)4 and pTPPF(EG)4 accumulated mainly in lysosomes whereas meta derivatives mTPP(EG)1-4 in the endoplasmic reticulum (ER). Position of ethylene glycol chain on the...
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Surface-enhanced resonance Raman scattering of Zn(II) porphyrins in systems with aggregated and non-aggregated Ag nanoparticles
Spáčil, Dušan ; Vlčková, Blanka (advisor) ; Procházka, Marek (referee)
In this diploma thesis, SERRS(Surface - enhanced resonance Raman Scattering) and SERS (Surface - enhanced Raman Scattering), surface of plasmon extinction spectra and TEM images of systems with tetracationic zinc porphyrin ZnTMPyP and silver nanoparticles (Ag NPs) were studied and interpreted. The systems with isolated nanoparticles and the systems with compact aggregates were investigated. The systems with isolated nanoparticles were prepared by addition of ZnTMPyP to hydrosol of Ag NPs. NaCl was added to this system and so compact aggregates were prepared. SERRS and SERS spectra of ZnTMPyP were studied at excitation wavelengths λexc= 441.6 nm a 532 nm. Firstly, stationary systems and secondly dynamic development of hydrosol Ag NPs → Ag NPs/ ZnTMPyP → Ag NPs/ ZnTMPyP/ NaCl systems for 680 s was investigated. Time evolution of SERRS and SERS spectra were analyzed by factor analysis (FA) and time evolution of spectra extinction plasmon were measured. FA showed a strong increase of the signal of ZnTMPyP after the addition of NaCl, i.e. after conversion of isolated nanoparticles to compact aggregates. In these systems with high concentration of ZnTMPyP the increase of signal was succeeded by its decreased. With help of FA the limit of SERRS spectral detection (λexc= 441,6 nm) and limit of SERS spectral...
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