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1.
Inorg Chem ; 59(2): 1242-1255, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31910004

RESUMO

Cytochrome c oxidase (CcO) has a binuclear active site composed of a high-spin heme group and a tris-histidine-ligated copper ion (CuB). By using two different porphyrin models derived by Gunter (H2TPyPP) and us (H2TImPP), we have isolated several mono- and binuclear complexes including one carbonyl and three chloride derivatives which are determined by 100 K single-crystal X-ray. Low-temperature (4 K) EPR and multitemperature (295-25 K) Mössbauer investigations on the products not only confirmed the spin states of the two metal ions (S = 5/2 Fe3+ and S = 1/2 Cu2+) but also revealed the intermolecular interactions and intramolecular couplings which are in accordance with the crystal structural features.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/análise , Porfirinas/química , Cristalografia por Raios X , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Modelos Moleculares , Estrutura Molecular , Porfirinas/metabolismo , Temperatura Ambiente
2.
Chem Soc Rev ; 49(3): 865-907, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31957756

RESUMO

Supramolecular chemistry is a central topic in modern chemistry. It touches on many traditional disciplines, such as organic chemistry, inorganic chemistry, physical chemistry, materials chemistry, environmental chemistry, and biological chemistry. Supramolecular hosts, inter alia macrocyclic hosts, play critical roles in supramolecular chemistry. Calix[4]pyrroles, non-aromatic tetrapyrrolic macrocycles defined by sp3 hybridized meso bridges, have proved to be versatile receptors for neutral species, anions, and cations, as well as ion pairs. Compared to the parent system, octamethylcalix[4]pyrrole and its derivatives bearing simple appended functionalities, strapped calix[4]pyrroles typically display enhanced binding affinities and selectivities. In this review, we summarize advances in the design and synthesis of strapped calix[4]pyrroles, as well as their broad utility in molecular recognition, supramolecular extraction, separation technology, ion transport, and as agents capable of inhibiting cancer cell proliferation. Future challenges within this sub-field are also discussed.


Assuntos
Calixarenos/química , Calixarenos/metabolismo , Porfirinas/química , Porfirinas/metabolismo , Ânions/química , Apoptose , Cátions/química , Permeabilidade da Membrana Celular , Cristalização , Modelos Moleculares , Estrutura Molecular , Compostos Orgânicos/química , Relação Estrutura-Atividade , Termodinâmica
3.
J Photochem Photobiol B ; 202: 111725, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790880

RESUMO

Photodynamic therapy (PDT) is an expanding treatment modality due to its minimally invasive localized activity and few adverse effects. This therapy requires photosensitive compounds, which have high sensitivity to light exposure. Thus, in this work, the in vitro antitumor activity of meso-tetra(3- and 4-pyridyl)porphyrins (3-TPyP and 4-TPyP) in metastatic melanoma cell (WM1366 line) and non-tumoral Ovarian lineage Chinese Hamister (CHO) was evaluated using photodynamic process. Cell viability tests, molecular docking, annexin V, confocal microscopy and qRT-PCR were performed. Our results show that both porphyrins inhibited the viability of metastatic melanoma cells when exposed to light and did not alter viability in the dark. In addition, they did not demonstrate cytotoxicity in non-tumor cells. Molecular coupling demonstrated platinum porphyrin affinity for the N-terminal region of APO B-100, LDL receptor, and therefore of the cells under study. Genes such as Caspase 3 and 9, P21, Bax / BCL2, MnSod and GSH showed increased expression. For meta isomer 3-PtTPyP treatment, caspase-9 and caspase-3 expression levels showed a 4.89 and 3.23-fold increase, respectively, while for the para isomer 4-PtTPyP, this change was 3.77 and 12.16-fold, respectively. We also observed an upregulated expression of p21, a protein well-known by its action in cell cycle arrest in a p53-dependent manner. Conclusion: 3-PtTPyP and 4-PtTPyP demonstrated antitumor effect on WM1366 cells, inducing apoptosis and significant alteration of cell cytoskeleton actin. Our work shows that platinum(II) porphyrins may be promising photosensitizers for the treatment of metastatic melanoma by PDT.


Assuntos
Portadores de Fármacos/química , Fármacos Fotossensibilizantes/química , Platina/química , Porfirinas/química , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Células CHO , Caspase 3/genética , Caspase 3/metabolismo , Cátions/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Luz , Melanoma/metabolismo , Melanoma/patologia , Simulação de Acoplamento Molecular , Fármacos Fotossensibilizantes/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
4.
J Photochem Photobiol B ; 202: 111703, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31810036

RESUMO

Despite the continuous development of medicine, there is still a lack of effective and fully safe protocols for the treatment of neoplastic diseases. The drug-drug conjugates approach seems to give a chance to obtain more efficient molecules. New alkoxy and metronidazole substituted porphyrins were synthesized. Novel porphyrins were purified by flash column chromatography and characterized using NMR, MS, UV-Vis and HPLC. The Nuclear Magnetic Resonance study was performed to annotate experimentally observed 1H NMR and 13C NMR signals of new compounds. The 2D NMR techniques such as 1H-1H COSY (Correlation Spectroscopy), 1H-13C HSQC (Heteronuclear Single Quantum Correlation) and 1H-13C HMBC (Heteronuclear Multiple Bond Correlation) were used for the structure elucidation of the new compounds. In the range of 250-450 nm of the absorption spectra, the Soret band was observed, whereas the Q band was noted in the range of 500-650 nm. Compounds revealed a fluorescence quantum yield in the range 0.03-0.12. Singlet oxygen generation quantum yields up to 0.54 were determined. Electrochemical properties has also been studied. It has been noticed electropolymerization of compound bearing 5-nitroimidazole substituents. The photodynamic activity of the studied porphyrins against A549 and HEK001/HPV16 cancer cells were examined. The most active against A549 and HEK 001/HPV16 was light-excited trioxanonylporphyrin with the values of IC50 equal to 0.49 µM and 50 nM respectively.


Assuntos
Nitroimidazóis/química , Fármacos Fotossensibilizantes/química , Porfirinas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas Eletroquímicas , Humanos , Luz , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Porfirinas/farmacologia , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo
5.
Talanta ; 207: 120300, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594586

RESUMO

A "signal-on" chemiluminescence biosensor was established for detecting thrombin. The thrombin aptamer1-functionalized magnetic sodium alginate (Malg-Apt1) hydrogel was synthesized by physical interaction between sodium alginate and Ca2+, and it was used in the biosensor for separating and enriching thrombin. Ethylenediamine tetraacetic acid (EDTA) was used to chelate with Ca2+ to dissolve the hydrogel and release thrombin. A metalloporphyrinic metal-organic framework nanosheet, named as Cu-TCPP(Co) MOFs, was prepared as signal amplification strategy. Cu-TCPP(Co) MOFs/Au-ssDNA (ssDNA: single-strand DNA) was synthesized for controllable further amplification of chemiluminescent signal. The thrombin aptamer2-functionalized magnetic carbon nanotubes (MCNTs-Apt2) were used as a matrix, and Cu-TCPP(Co) MOFs/Au-ssDNA was adsorbed on the MCNTs by the complementary pairing of the partial bases between ssDNA and Apt2. Compared with ssDNA, Apt2 has a stronger interaction with thrombin. Therefore, thrombin can trigger the release of Cu-TCPP(Co) MOFs/Au-ssDNA to achieve signal amplification. Under the optimal conditions, the biosensor could detect thrombin as low as 2.178 × 10-13 mol/L with the range from 8.934 × 10-13 to 5.956 × 10-10 mol/L and exhibited excellent selectively. Moreover, the "signal-on" chemiluminescence biosensor showed potential application for the detection of thrombin in body fluids.


Assuntos
Alginatos/química , Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/química , Hidrogéis/química , Estruturas Metalorgânicas/química , Nanotubos de Carbono/química , Trombina/análise , Adsorção , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Sequência de Bases , DNA de Cadeia Simples/genética , Medições Luminescentes , Imãs/química , Modelos Moleculares , Conformação Molecular , Porfirinas/química , Trombina/metabolismo
6.
Chemosphere ; 238: 124552, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31437631

RESUMO

An optical sensor membrane was prepared by electrostatic self-assembled technique for online detection of cadmium ion (II) (Cd(II)). The optical indicator 5,10,15,20-tetrakis(4-N-methylpyridyl) porphyrin p-toluenesulfonate (TMPyP) was adsorbed on a hydrolyzed polyacrylonitrile (PAN) membrane by electrostatic attraction and further immobilized through layer-by-layer deposition of poly(allylamine hydrochloride) (PAH) and poly(sodium 4-styrenesulfonate) (PSS) on the membrane surface. The electrostatic self-assembly of polyelectrolytes on the membrane is influenced by pH and salt concentration of polyelectrolytes. The optical sensor membrane shows distinct color and spectral response to Cd(II) under static and flow-through conditions based on the coordination of TMPyP with Cd(II). A faster detection of Cd(II) is achieved at higher feed concentration of Cd(II) or appropriate lower immobilization capacity of TMPyP on the membrane. The flow-through detection is also influenced by the flow rate; higher flow rate led to faster response to Cd(II) during filtration. Compared with the static process, the flow-through conditions are more conducive to faster analysis of ppb level concentration of Cd(II) (10-3 mg L-1) due to a promoted mass transfer and filtration enrichment. Hence, the development of the optical sensor membrane in this study demonstrated the prospect to make membranes multifunctional with advantages for online chromatic warning in addition to adsorption/rejection of heavy metal ions in the solutions that are treated.


Assuntos
Resinas Acrílicas/química , Técnicas Biossensoriais/métodos , Cádmio/análise , Membranas Artificiais , Fármacos Fotossensibilizantes/química , Polieletrólitos/química , Porfirinas/química , Adsorção , Eletricidade Estática
7.
Biomed Khim ; 65(6): 507-512, 2019 Oct.
Artigo em Russo | MEDLINE | ID: mdl-31876521

RESUMO

Cytotoxic and photoinduced activity of chlorine e6 (Ce6) in phospholipid nanoparticles with specific tumor targeting and cell-penetrating peptides was studied in vitro using human fibrosarcoma cells HT-1080. It was shown, that the binding of cell-penetrating peptide R7 - alone or combined with the peptide containing specific targeting motif NGR (Asn-Gly-Arg) - resulted in 3-fold decrease of Ce6 photoinduced activity as compared with that in nanoparticles without peptides (IC50 values were 0.7 µg/ml and 2.1 µg/ml, respectively). The NGR influence was unexpectedly low - less than 20% (IC50 1.7 µg/ml). This suggests the more importance of Ce6 cell penetration in this case, than of NGR-mediated targeting. The effect of inclusion of both peptides on the total cytotoxicity of Ce6 was minimal (10-16 times less than on the specific photoinduced activity). The obtained results - together with earlier shown effects on improvement of the pharmacokinetics of Ce6 in vivo after its embedding into phospholipid nanoparticles - indicate the prospects of using the obtained phospholipid nanoparticles system for photodynamic therapy.


Assuntos
Nanopartículas , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Fotoquimioterapia , Porfirinas/química , Linhagem Celular Tumoral , Humanos , Fármacos Fotossensibilizantes
8.
Phys Chem Chem Phys ; 21(45): 25054-25064, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31690919

RESUMO

Liposomes carrying membrane-embedded porphyrin-phospholipid (PoP) are capable of chemo- and photo-therapeutic modes of action, which make them a potential candidate material for next-generation cancer treatments. This study examines singlet oxygen (1O2) production and release by PoP liposomes carrying either no chemotherapeutic cargo (EMPTY), or those carrying either doxorubicin (DOX) or irinotecan (IRT) chemotherapy drugs. Herein, we developed a strategy to quantify the fraction of 1O2 lifetime spent in the three distinct local liposomal environments by obtaining four key pieces of information for each system: average 1O2 deactivation rate constants (kΔ) for liposome suspensions in H2O and in D2O solvents, as well as the absolute and the apparent 1O2 production quantum yields (ΦΔ). Despite the characteristic differences in their photophysical behavior, namely in ΦΔ values, all three formulations of PoP liposomes were found to carry out 1O2 release in a similar manner. It was found that >80% of all sensitized 1O2 from the ensemble of PoP liposomes deactivates within the nanostructures themselves, with the largest portion (∼50%) deactivating in the lipid membrane specifically. Based on these findings, we conclude that the current design of the PoP liposomes is well suited for light-induced chemotherapeutic drug release. Importantly, the 1O2 partition quantification approach reported herein has potential to be a tool for characterizing nanoparticulate light-activated chemo- and phototherapeutic systems.


Assuntos
Fosfolipídeos/química , Fotoquimioterapia , Oxigênio Singlete/química , Humanos , Lipossomos/química , Porfirinas/química
9.
Chem Commun (Camb) ; 55(96): 14534-14537, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31740902

RESUMO

Fe-N/C single atom catalysts (SACs) exhibit peroxidase-like, oxidase-like, catalase-like, and glutathione peroxidase-like activity. Fe-N/C SACs are successfully applied to control the intracellular H2O2 level. This study not only explores the types of SACs mimicking enzymes but also provides opportunities for SACs in biomedical and other bioengineering applications.


Assuntos
Materiais Biomiméticos/química , Carbono/química , Ferro/química , Nitrogênio/química , Espécies Reativas de Oxigênio/química , Materiais Biomiméticos/metabolismo , Materiais Biomiméticos/farmacologia , Catalase/química , Catalase/metabolismo , Catálise , Sobrevivência Celular/efeitos dos fármacos , Glutationa Peroxidase/química , Glutationa Peroxidase/metabolismo , Células HeLa , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Oxirredução , Porfirinas/química , Espécies Reativas de Oxigênio/metabolismo
10.
Photochem Photobiol Sci ; 18(12): 2854-2858, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31761915

RESUMO

Fluorescence intensities of water-soluble ß-(1,3-1,6)-d-glucan (ß-1,3-glucan)-complexed porphyrin derivatives were very weak as a result of self-quenching. However, ß-1,3-glucan-complexed tetra(aminophenyl)porphyrin exhibited 'off-state' to 'on-state' fluorescence switching activity by intracellular uptake. Furthermore, the internalised complex showed a high level of photodynamic activity toward HeLa cells under photoirradiation at long wavelengths.


Assuntos
Glucanos/química , Porfirinas/química , Células HeLa , Humanos , Luz , Microscopia de Fluorescência , Fotoquimioterapia , Porfirinas/metabolismo
11.
C R Biol ; 342(9-10): 279-289, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31780416

RESUMO

The ATP-Binding Cassette, subfamily G, member 2 (ABCG2) transporter is associated with the regulation of protoporphyrin IX transport and of other intermediates in heme biosynthesis. Because the hamster Harderian gland (HG) exhibits high concentrations of porphyrins and sexual dimorphism, we analyzed the hamster ABCG2. Cloned cDNA [2098-base pairs (bp)] contains an open-reading frame (ORF) of 1971-bp that encodes a 656 amino-acid protein with a molecular weight of 72844.56Da. The hamster ABCG2 sequence is conserved phylogenetically and shares a high percentage of identity with mouse (89%), rat (88%), and human (84%) transporters. Within its structure, a Walker A (G-X-X-G-X-G-K-S), a C signature motif characteristic of ABC transporters, and six putative transmembrane domains (TMDs) were identified. ABCG2 mRNA was detected in all hamster tissues, with higher amounts found in HG, brain, cerebellum, kidney, gut, ovary, and testis. Harderian ABCG2 expression exhibits a sexually dimorphic pattern where females display higher mRNA levels than males. Different patterns of transcriptional profiles of ABCG2 during the estrous cycle and after gonadectomy in both sexes were also observed. The differential expression between male and female HGs suggests that ABCG2 is under the regulation of gonadal steroids. The ABCG2 transporter is likely involved in the endogenous regulation of porphyrins in hamster HGs.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Glândula de Harder/metabolismo , Protoporfirinas/metabolismo , Animais , Cricetinae , DNA Complementar , Feminino , Humanos , Masculino , Mesocricetus , Camundongos , Porfirinas/metabolismo , RNA Mensageiro , Ratos , Caracteres Sexuais
13.
Chem Commun (Camb) ; 55(97): 14558-14565, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31748764

RESUMO

The association of hydrophobic cavities with porphyrin derivatives has been used to mimic haemoprotein structures. The most employed cavity in this field is ß-cyclodextrin (ß-CD), and scaffolds combining ß-CDs and porphyrins are expected to inspire the combination of porphyrins and cucurbiturils in the near future. Aside from providing water solubility to various porphyrinic structures, the ß-CD framework can also modulate and control the reactivity of the metal core of the porphyrin. After a general introduction of the challenges faced in the field of haemoprotein models and the binding behavior of ß-CDs, this article will discuss covalent and non-covalent association of porphyrins with ß-CDs. In each approach, the role of the CD differs according to the relative position of the concave CD host, either directly controlling the binding and transformation of a substrate on the metalloporphyrin or playing a dual role of controlling the water solubility and selecting the axial ligand of the metal core. The discussion will be of interest to the cucurbituril community as well as to the cavitand community, as the information provided should be useful for the design of haemoprotein mimics using cucurbiturils.


Assuntos
Ciclodextrinas/química , Hemeproteínas/química , Modelos Moleculares , Porfirinas/química , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Estrutura Molecular , Solubilidade , Água/química
14.
Chem Commun (Camb) ; 55(95): 14255-14258, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31657388
15.
Nanoscale ; 11(39): 18426-18435, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31576881

RESUMO

This work explored the application of matrix metalloproteinase 2-targeted superparamagnetic nanoprobes for magnetic resonance imaging (MRI), near infrared (NIR) fluorescence imaging and photodynamic therapy of tumors. PEG, PAMAM (G5) and matrix metalloproteinase 2 (MMP2) were attached to the surface of carboxylated Fe3O4 nanoparticles (NPs) using a chemical coupling method and then finally loaded with the photosensitizer chlorin e6 (Ce6). In vitro and in vivo experiments demonstrated that the Fe3O4-PEG-G5-MMP2@Ce6 nanoprobes exhibited excellent stability, precise tumor targeting and biocompatibility. Furthermore, the fluorescence properties of Fe3O4-PEG-G5-MMP2@Ce6 nanoprobes were analogous to Ce6 and could be employed for fluorescence imaging. Meanwhile, the Fe3O4-PEG-G5-MMP2@Ce6 nanoprobes have also been shown to be effective as contrast agents for T2-weighted MRI. The target molecule MMP2 enhanced the tumor targeting ability of Fe3O4-PEG-G5-MMP2@Ce6 nanoprobes. Additionally, the Fe3O4-PEG-G5-MMP2@Ce6 nanoprobes significantly inhibited tumor growth compared with PBS and free Ce6. This work will inspire greater enthusiasm for the construction of multifunctional magnetic nanoplatforms for biomedical applications.


Assuntos
Nanopartículas de Magnetita , Neoplasias Experimentais , Imagem Óptica , Fotoquimioterapia , Fármacos Fotossensibilizantes , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Metaloproteinase 2 da Matriz/química , Metaloproteinase 2 da Matriz/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
16.
ACS Appl Mater Interfaces ; 11(41): 37461-37470, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31577423

RESUMO

An important objective of cancer nanomedicine is to improve the delivery efficacy of functional agents to solid tumors for effective cancer imaging and therapy. Stimulus-responsive nanoplatforms can target and regulate the tumor microenvironment (TME) for the optimization of cancer theranostics. Here, we developed magnetic manganese oxide sweetgum-ball nanospheres (MMOSs) with large mesopores as tools for improved cancer theranostics. MMOSs contain magnetic iron oxide nanoparticles and mesoporous manganese oxide (MnO2) nanosheets, which are assembled into gumball-like structures on magnetic iron oxides. The large mesopores of MMOSs are suited for cargo loading with chlorin e6 (Ce6) and doxorubicin (DOX), thus producing so-called CD@MMOSs. The core of magnetic iron oxides could achieve magnetic targeting of tumors under a magnetic field (0.25 mT), and the targeted CD@MMOSs may decompose under TME conditions, thereby releasing loaded cargo molecules and reacting with endogenous hydrogen peroxide (H2O2) to generate oxygen (O2) and manganese (II) ions (Mn2+). Investigation in vivo in tumor-bearing mice models showed that the CD@MMOS nanoplatforms achieved TME-responsive cargo release, which might be applied in chemotherapy and photodynamic therapy. A remarkable in vivo synergy of diagnostic and therapeutic functionalities was achieved by the decomposition of CD@MMOSs and coadministration with chemo-photodynamic therapy of tumors using the magnetic targeting mechanism. Thus, the result of this study demonstrates the feasibility of smart nanotheranostics to achieve tumor-specific enhanced combination therapy.


Assuntos
Doxorrubicina , Nanopartículas de Magnetita , Compostos de Manganês , Nanosferas , Neoplasias Experimentais/tratamento farmacológico , Óxidos , Porfirinas , Microambiente Tumoral/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Feminino , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Nanomedicina , Nanosferas/química , Nanosferas/uso terapêutico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Óxidos/química , Óxidos/farmacologia , Porosidade , Porfirinas/química , Porfirinas/farmacologia
17.
Photochem Photobiol Sci ; 18(11): 2792-2803, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626259

RESUMO

We report the first exocyclically metallated tetrapyridinoporphyrazine, [tetrakis-(trans-Pt(NH3)2Cl)-tetra(3,4-pyrido)porphyrazine-zinc(ii)](NO3)4 (4), synthesized in a multistep synthesis starting from 3,4-pyridinedicarbonitrile (1). The synthetic procedure involved a platination reaction of the intermediate tetra(3,4-pyrido)porphyrazine-zinc(ii) (2), whereby the zinc(ii) enhanced the solubility of the intermediate enabling the platination reaction. A similar approach to synthesize [tetrakis-(trans-Pt(NH3)2Cl)-tetra(3,4-pyrido)porphyrazine](NO3)4 (5) failed due to the unsuitable solubility properties of the intermediate tetra(3,4-pyrido)porphyrazine (3). The final product 4 and the intermediates were characterized, the photochemical and photophysical properties were determined and the photocytotoxicities were investigated. We demonstrate that the platinated tetra-pyridinoporphyrazine 4 is a potential photosensitizer for photodynamic therapy (PDT).


Assuntos
Fármacos Fotossensibilizantes/química , Porfirinas/química , Zinco/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Luz , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Fluorescência , Estereoisomerismo
18.
Chem Commun (Camb) ; 55(94): 14103-14106, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31603154

RESUMO

In this work, the self assembly ability of chromophores covalently linked to aliphatic dipeptides is described. Altering various parameters such as the protecting group, the solvent mixture, the dipeptide and the chromophore resulted in different nanostructures. Interestingly, a peptide-porphyrin hybrid is capable of forming a hydrogel in HFIP-water solvent mixture.


Assuntos
Compostos de Boro/química , Dipeptídeos/química , Nanoestruturas/química , Porfirinas/química , Estrutura Molecular , Tamanho da Partícula , Propanóis/química , Solventes/química , Propriedades de Superfície , Água/química
19.
Anal Chim Acta ; 1089: 66-77, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31627820

RESUMO

The dehydration reaction of tetraamino porphyrin and 4,4'-biphenyldicarboxaldehyde was performed for the synthesis of a novel covalent organic framework (COF), which was decorated on magnetic Fe3O4 to obtain core-shell structured Fe3O4@COFs nanospheres for the first time, for effective extraction and enrichment of sulfonamides (SAs). The morphology and structure of the synthesized nanospheres were characterized through various methods. The extraction conditions for six SAs including sulfadiazine, sulfamerazine, sulfamethazine, sulfamonomethoxine, sulfamethoxazole, sulfadimethoxine were systematically optimized. Fe3O4@COFs nanospheres were evaluated for magnetic solid-phase extraction. By coupling with high-performance liquid chromatography, a facile and sensitive method was established for the quantitation analysis of six SAs. The method showed good linearity ranging from 1 to 500 ng mL-1 with R2 > 0.99, high sensitivity with LODs in the range of 0.2-1 ng mL-1, and high precision with RSDs≤6.3%. This method was further applied into determination of SAs in environmental water and food samples, with recoveries in the range of 65.3%-107.3% and RSDs≤6.7%. These successful applications suggest that the core-shell structured Fe3O4@COFs nanospheres could be used as a potential adsorbent for efficient extraction and analysis of trace SAs.


Assuntos
Contaminação de Alimentos/análise , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Porfirinas/química , Sulfonamidas/análise , Poluentes Químicos da Água/análise , Adsorção , Animais , Galinhas , Lagos/análise , Limite de Detecção , Estruturas Metalorgânicas/síntese química , Leite/química , Penaeidae , Porfirinas/síntese química , Frutos do Mar/análise , Extração em Fase Sólida/métodos
20.
Biofouling ; 35(7): 742-757, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31550929

RESUMO

The self-produced extracellular polymeric matrix of biofilms renders them difficult to eliminate once they are established. This makes the inhibition of biofilm formation key to successful treatment of biofilm infection. Antimicrobial photodynamic therapy (aPDT) and antimicrobial peptides offer a new approach as antibiofilm strategies. In this study sub-lethal doses of aPDT (with chlorin-e6 (Ce6-PDT) or methylene blue (MB-PDT)) and the peptides AU (aurein 1.2 monomer) or (AU)2K (aurein 1.2 C-terminal dimer) were combined to evaluate their ability to prevent biofilm development by Enterococcus faecalis. Biofilm formation was assessed by resazurin reduction, confocal microscopy, and infrared spectroscopy. All treatments successfully prevented biofilm development. The (AU)2K dimer had a stronger effect, both alone and combined with aPDT, while the monomer AU had significant activity when combined with Ce6-PDT. Additionally, it is shown that the peptides bind to the lipoteichoic acid of the E. faecalis cell wall, pointing to a possible key mechanism of biofilm inhibition.


Assuntos
Antibacterianos/química , Biofilmes , Peptídeos/química , Fármacos Fotossensibilizantes/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Peptídeos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química
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