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1.
Pharm Res ; 37(10): 193, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32914377

RESUMO

PURPOSE: The incidence of breast cancer worldwide has been on the rise since the late 1970s, and it has become a common tumor that threatens women's health. Aminoglutethimide (AG) is a common treatment of breast cancer. However, current treatments require frequent dosing that results in unstable plasma concentration and low bioavailability, risking serious adverse reactions. Our goal was to develop a molecularly imprinted polymer (MIP) based delivery system to control the release of AG and demonstrate the availability of this drug delivery system (DDS), which was doped with carbon nanotube with aid of metal-organic gel. METHODS: Preparation of MIP was optimized by key factors including composition of formula, ratio of monomers and drug loading concentration. RESULTS: By using multi-walled carbon nanotubes (MWCNT) and metal-organic gels (MOGs), MIP doubled the specific surface area, pore volume tripled and the IF was 1.6 times than the reference. Compared with commercial tablets, the relative bioavailability was 143.3% and a more stable release appeared. CONCLUSIONS: The results highlight the influence of MWCNT and MOGs on MIP, which has great potential as a DDS.


Assuntos
Aminoglutetimida/química , Antineoplásicos Hormonais/química , Complexos de Coordenação/química , Sistemas de Liberação de Medicamentos/métodos , Nanotubos de Carbono/química , Aminoglutetimida/administração & dosagem , Aminoglutetimida/farmacocinética , Animais , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/farmacocinética , Complexos de Coordenação/administração & dosagem , Compostos Férricos/química , Géis/administração & dosagem , Géis/química , Humanos , Células MCF-7 , Masculino , Impressão Molecular/métodos , Ratos , Ácidos Tricarboxílicos/química
2.
Yakugaku Zasshi ; 140(8): 955-960, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741867

RESUMO

A nickel-aluminium-zirconium complex-layered hydroxide (NAZ), which was synthesized using each inorganic sulfate mixing ratio of 0.9 : 1.0 : 0.1, was prepared and calcined at different temperatures. The physicochemical properties of the NAZ were analyzed by scanning electron microscopy, specific surface area, number of hydroxyl groups, and pore volume. The specific surface area, number of hydroxyl groups, and pore volume of NAZ was 51.9 m2/g, 1.08 mmol/g, and 0.27 µL/g, respectively. The amount of phosphate ion adsorbed onto NAZ was higher than that onto calcined NAZ at different temperatures. Therefore, the interaction between phosphate ions and NAZ was assessed using the elemental distribution analysis and the binding energy. After adsorption, the intensity of phosphorus atoms increased, indicating that the phosphate ions were adsorbed onto the NAZ surface. Additionally, phosphorus peaks (189 eV for 2s and 130 eV for 2p), which were not detected before adsorption, were clearly detected after adsorption. On the other hand, the intensity of the sulfur peak (165 eV for 2p) decreased after adsorption. Thus, we evaluated the ion exchange between phosphate ion and sulfate ion in the interlayer space of the NAZ. As a result, the correlation coefficient between the amount of phosphate ion adsorbed and the amount of sulfate ion released was positively correlated (r=0.960). Therefore, it can be clearly stated that one of the adsorption mechanisms of phosphate ions was related to ion exchange in the interlayer space of the NAZ. These findings are useful for preventing the eutrophication and recovery of phosphate ion in water environments.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Hidróxidos/química , Hidróxidos/síntese química , Fosfatos/química , Adsorção , Alumínio , Fenômenos Químicos , Eutrofização , Troca Iônica , Íons , Microscopia Eletroquímica de Varredura , Níquel , Zircônio
3.
Acta Crystallogr C Struct Chem ; 76(Pt 7): 663-672, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32624513

RESUMO

The reactivity of the cobalt(III) complexes dichlorido[tris(2-aminoethyl)amine]cobalt(III) chloride, [CoCl2(tren)]Cl, and dichlorido(triethylenetetramine)cobalt(III) chloride, [CoCl2(trien)]Cl, towards different amino acids (L-proline, L-asparagine, L-histidine and L-aspartic acid) was explored in detail. This study presents the crystal structures of three amino acidate cobalt(III) complexes, namely, (L-prolinato-κ2N,O)[tris(2-aminoethyl)amine-κ4N,N',N'',N''']cobalt(III) diiodide monohydrate, [Co(C5H8NO2)(C6H18N4)]I2·H2O, I, (L-asparaginato-κ2N,O)[tris(2-aminoethyl)amine-κ4N,N',N'',N''']cobalt(III) chloride perchlorate, [Co(C4H7N2O3)(C6H18N4)](Cl)(ClO4), II, and (L-prolinato-κ2N,O)(triethylenetetramine-κ4N,N',N'',N''')cobalt(III) chloride perchlorate, [Co(C4H7N2O3)(C6H18N4)](Cl)(ClO4), V. The syntheses of the complexes were followed by characterization using UV-Vis spectroscopy of the reaction mixtures and the initial rates of reaction were obtained by calculating the slopes of absorbance versus time plots. The initial rates suggest a stronger reactivity and hence greater affinity of the cobalt(III) complexes towards basic amino acids. The biocompatibility of the complexes was also assessed by evaluating the cytotoxicity of the complexes on cultured normal human fibroblast cells (WS1) in vitro. The compounds were found to be nontoxic after 24 h of incubation at concentrations up to 25 mM.


Assuntos
Cobalto/química , Complexos de Coordenação/química , Histidina/química , Aminoácidos/química , Cristalografia por Raios X , Ligantes , Percloratos/química
4.
Proc Natl Acad Sci U S A ; 117(30): 17535-17542, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32661159

RESUMO

Mismatch repair (MMR) deficiencies are a hallmark of various cancers causing accumulation of DNA mutations and mismatches, which often results in chemotherapy resistance. Metalloinsertor complexes, including [Rh(chrysi)(phen)(PPO)]Cl2 (Rh-PPO), specifically target DNA mismatches and selectively induce cytotoxicity within MMR-deficient cells. Here, we present an in vivo analysis of Rh-PPO, our most potent metalloinsertor. Studies with HCT116 xenograft tumors revealed a 25% reduction in tumor volume and 12% increase in survival with metalloinsertor treatment (1 mg/kg; nine intraperitoneal doses over 20 d). When compared to oxaliplatin, Rh-PPO displays ninefold higher potency at tumor sites. Pharmacokinetic studies revealed rapid absorption of Rh-PPO in plasma with notable accumulation in the liver compared to tumors. Additionally, intratumoral metalloinsertor administration resulted in enhanced anticancer effects, pointing to a need for more selective delivery methods. Overall, these data show that Rh-PPO inhibits xenograft tumor growth, supporting the strategy of using Rh-PPO as a chemotherapeutic targeted to MMR-deficient cancers.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Ródio , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacocinética , Pareamento Incorreto de Bases/efeitos dos fármacos , Complexos de Coordenação/administração & dosagem , Complexos de Coordenação/química , Complexos de Coordenação/farmacocinética , Reparo de Erro de Pareamento de DNA/efeitos dos fármacos , Modelos Animais de Doenças , Células HCT116 , Humanos , Camundongos , Estrutura Molecular , Ródio/química , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nat Commun ; 11(1): 3262, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591538

RESUMO

The use of photodynamic therapy (PDT) against cancer has received increasing attention over recent years. However, the application of the currently approved photosensitizers (PSs) is limited by their poor aqueous solubility, aggregation, photobleaching and slow clearance from the body. To overcome these limitations, there is a need for the development of new classes of PSs with ruthenium(II) polypyridine complexes currently gaining momentum. However, these compounds generally lack significant absorption in the biological spectral window, limiting their application to treat deep-seated or large tumors. To overcome this drawback, ruthenium(II) polypyridine complexes designed in silico with (E,E')-4,4'-bisstyryl-2,2'-bipyridine ligands show impressive 1- and 2-Photon absorption up to a magnitude higher than the ones published so far. While nontoxic in the dark, these compounds are phototoxic in various 2D monolayer cells, 3D multicellular tumor spheroids and are able to eradicate a multiresistant tumor inside a mouse model upon clinically relevant 1-Photon and 2-Photon excitation.


Assuntos
Complexos de Coordenação/uso terapêutico , Desenho de Fármacos , Fotoquimioterapia , Fótons , Rutênio/química , Animais , Proliferação de Células , Sobrevivência Celular , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Feminino , Células HeLa , Humanos , Camundongos Nus , Oxigênio Singlete/química , Análise Espectral , Esferoides Celulares/patologia
6.
Pharm Res ; 37(6): 91, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385723

RESUMO

PURPOSE: Bevacizumab (BCZ) is a recombinant monoclonal antibody that inhibits the biological activity of the vascular endothelial growth factor, which has an important role in angiogenesis for tumoral growth and progression. In this way, our objective was to develop chitosan-coated lipid-core nanocapsules functionalized with BCZ by an organometallic complex using gold-III. METHODS: The formulation was produced and characterized in relation to physicochemical characteristics. Furthermore, the antitumoral and antiangiogenic activities were evaluated against C6 glioma cell line and chicken embryo chorioallantoic membrane (CAM), respectively. RESULTS: Final formulation showed nanometric size, narrow polydispersity, positive zeta potential and gold clusters size lower than 2 nm. BCZ in aqueous solution (0.01-0.10 µmol L-1) did not show cytotoxic activity in vitro against C6 glioma cell line; although, MLNC-Au-BCZ showed cytotoxicity with a median inhibition concentration of 30 nmol L-1 of BCZ. Moreover, MLNC-Au-BCZ demonstrated cellular internalization dependent on incubation time and BCZ concentration. BCZ solution did not induce significant apoptosis as compared to MLNC-Au-BCZ within 24 h of treatment. CAM assay evidenced potent antiangiogenic activity for MLNC-Au-BCZ, representing a decrease of 5.6 times in BCZ dose comparing to BCZ solution. CONCLUSION: MLNC-Au-BCZ is a promising product for the treatment of solid tumors.


Assuntos
Inibidores da Angiogênese/química , Bevacizumab/química , Quitosana/química , Glioma/tratamento farmacológico , Ouro/química , Lipídeos/química , Nanocápsulas/química , Inibidores da Angiogênese/farmacologia , Animais , Apoptose/efeitos dos fármacos , Bevacizumab/metabolismo , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Embrião de Galinha , Membrana Corioalantoide/efeitos dos fármacos , Complexos de Coordenação/química , Relação Dose-Resposta a Droga , Composição de Medicamentos/métodos , Hexoses/química , Humanos , Lectinas de Plantas/química , Polissorbatos/química , Proteínas de Soja/química , Propriedades de Superfície , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Chemistry ; 26(40): 8676-8688, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32452579

RESUMO

Resistance to chemotherapy is a current clinical problem, especially in the treatment of microbial infections and cancer. One strategy to overcome this is to make new derivatives of existing drugs by conjugation to organometallic fragments, either by an appropriate linker, or by direct coordination of the drug to a metal. We illustrate this with examples of conjugated organometallic metallocene sandwich and half-sandwich complexes, RuII and OsII arene, and RhIII and IrIII cyclopentadienyl half-sandwich complexes. Ferrocene conjugates are particularly promising. The ferrocene-chloroquine conjugate ferroquine is in clinical trials for malaria treatment, and a ferrocene-tamoxifen derivative (a ferrocifen) seems likely to enter anticancer trails soon. Several other examples illustrate that organometallic conjugation can restore the activity of drugs to which resistance has developed.


Assuntos
Aminoquinolinas/química , Antimaláricos/uso terapêutico , Cloroquina/farmacologia , Complexos de Coordenação/química , Compostos Ferrosos/química , Malária/tratamento farmacológico , Metalocenos/química , Compostos Organometálicos/química , Compostos de Rutênio/farmacologia , Antimaláricos/farmacologia , Cloroquina/química , Complexos de Coordenação/uso terapêutico , Humanos , Estrutura Molecular , Compostos de Rutênio/síntese química
8.
Biofouling ; 36(3): 351-367, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32401555

RESUMO

Pseudomonas aeruginosa and Serratia marcescens are prominent members belonging to the group of ESKAPE pathogens responsible for Urinary Tract Infections (UTI) and nosocomial infections. Both the pathogens regulate several virulence factors, including biofilm formation through quorum sensing (QS), an intercellular communication mechanism. The present study describes the anti-biofilm and QS quenching effect of thiazolinyl-picolinamide based palladium(II) complexes against P. aeruginosa and S. marcescens. Palladium(II) complexes showed quorum sensing inhibitory potential in inhibiting swarming motility behaviour, pyocyanin production and other QS mediated virulence factors in both P. aeruginosa and S. marcescens. In addition, the establishment of biofilms was prevented on palladium (II) coated catheters. Overall, the present study demonstrates that thiazolinyl-picolinamide based palladium (II) complexes will be a promising strategy to combat device-mediated UTI infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Paládio/farmacologia , Ácidos Picolínicos/química , Tiazóis/química , Cateteres Urinários/microbiologia , Antibacterianos/química , Antibacterianos/toxicidade , Biofilmes/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/toxicidade , Infecção Hospitalar/prevenção & controle , Humanos , Células MCF-7 , Paládio/química , Paládio/toxicidade , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Piocianina/metabolismo , Percepção de Quorum/efeitos dos fármacos , Serratia marcescens/efeitos dos fármacos , Serratia marcescens/metabolismo , Infecções Urinárias/microbiologia , Infecções Urinárias/prevenção & controle , Virulência , Fatores de Virulência/metabolismo
9.
Food Chem ; 326: 126988, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32447162

RESUMO

In this study, a simple and quick ionic liquid- based ultrasonic-assisted microextraction (IL-UA-ME) procedure has been improved for extraction of melamine in dairy productsfollowed by UV-VIS spectrometry. For the analysis of stability and reactivity of melamine and its some metal complexes, quantum chemical parameters like frontier orbital energy-HOMO-LUMO energy gap, hardness and softness were calculated using computational chemistry tools. The results regarding to stability analysis made considering density functional theory showed that theoretical data obtained are compatible with experimentally obtained results, and Fe-melamine complex is more stable compared to others. Under optimum conditions, the linearity was in the range of 0.05-400 ng mL-1 with detection limit of 0.015 ng mL-1. Following the validation studies, recovery and relative standard deviation were obtained in range of 92.5-104.3% and 1.4-2.1%, respectively. The first research article in which experimental and theoretical studies are used together for the determination of melamine in dairy products.


Assuntos
Laticínios/análise , Líquidos Iônicos/química , Triazinas/análise , Complexos de Coordenação/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Teoria Quântica , Microextração em Fase Sólida , Sonicação , Temperatura , Triazinas/química , Triazinas/isolamento & purificação
10.
Acta Crystallogr C Struct Chem ; 76(Pt 5): 476-482, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32367829

RESUMO

Reaction of N,N'-(cyclohexane-1,2-diylidene)bis(4-fluorobenzohydrazide), C20H18F2N4O2, (LF), with zinc chloride and mercury(II) chloride produced different types and shapes of neutral coordination complexes, namely, dichlorido[N,N'-(cyclohexane-1,2-diylidene)bis(4-fluorobenzohydrazide)-κ2N,O]zinc(II), [ZnCl2(C20H18F2N4O2)], (1), and dichlorido[N,N'-(cyclohexane-1,2-diylidene)bis(4-fluorobenzohydrazide)-κ4O,N,N',O']mercury(II), [HgCl2(C20H18F2N4O2)], (2). The organic ligand and its metal complexes are characterized using various techniques: IR, UV-Vis and nuclear magnetic resonance (NMR) spectroscopies, in addition to powder X-ray diffraction (PXRD), single-crystal X-ray crystallography and microelemental analysis. Depending upon the data from these analyses and measurements, a typical tetrahedral geometry was confirmed for zinc complex (1), in which the ZnII atom is located outside the bis(benzhydrazone) core. The HgII atom in (2) is found within the core and has a common octahedral structure. The in vitro antibacterial activities of the prepared compounds were evaluated against two different bacterial strains, i.e. gram positive Bacillus subtilis and gram negative Pseudomonas aeruginosa bacteria. The prepared compounds exhibited differentiated growth-inhibitory activities against these two bacterial strains based on the difference in their lipophilic nature and structural features.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Cloretos/farmacologia , Mercúrio/química , Compostos de Zinco/farmacologia , Zinco/química , Antibacterianos/química , Cloretos/química , Complexos de Coordenação/química , Cristalografia por Raios X , Difração de Raios X , Compostos de Zinco/química
11.
Dalton Trans ; 49(19): 6249-6258, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32329503

RESUMO

Copper-based radiopharmaceuticals are of high interest these days owing to the decay properties of copper radioisotopes. In contrast, labeled zinc compounds have been less studied for applications in nuclear medicine. In this study, the stability of labeled zinc and copper complexes with two azacrown ether ligands was investigated and compared. Then, the in vitro and in vivo stability of the studied zinc complexes was demonstrated, with the complexes showing promise for biomedical applications. In contrast, analogous copper complexes quickly dissociated in the presence of serum proteins. Furthermore, a simple method for the production of radiochemically pure 65Zn was proposed, and the opportunity for its use as a surrogate radionuclide for research into potential zinc-containing radiopharmaceuticals was demonstrated.


Assuntos
Complexos de Coordenação/química , Cobre/química , Éteres de Coroa/química , Zinco/química , Animais , Complexos de Coordenação/sangue , Complexos de Coordenação/urina , Cristalografia por Raios X , Ligantes , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Radioisótopos de Zinco/química
12.
J Vis Exp ; (157)2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32250360

RESUMO

Chemical model complexes are prepared to represent the active site of an enzyme. In this protocol, a family of tridentate pincer ligand precursors (each possessing two sulfur and one nitrogen donor atom functionalities (SNS) and based on bis-imidazole or bis-triazole compounds) are metallated with CoCl2·6H2O to afford tridentate SNS pincer cobalt(II) complexes. Preparation of the cobalt(II) model complexes for liver alcohol dehydrogenase is facile. Based on a quick color change upon adding the CoCl2·6H2O to acetonitrile solution that contains the ligand precursor, the complex forms rapidly. Formation of the metal complex is complete after allowing the solution to reflux overnight. These cobalt(II) complexes serve as models for the zinc active site in liver alcohol dehydrogenase (LADH). The complexes are characterized using single crystal X-ray diffraction, electrospray mass spectrometry, ultra-violet visible spectroscopy, and elemental analysis. To accurately determine the structure of the complex, its single crystal structure must be determined. Single crystals of the complexes that are suitable for X-ray diffraction are then grown via slow vapor diffusion of diethyl ether into an acetonitrile solution that contains the cobalt(II) complex. For high quality crystals, recrystallization typically takes place over a 1 week period, or longer. The method can be applied to the preparation of other model coordination complexes and can be used in undergraduate teaching laboratories. Finally, it is believed that others may find this recrystallization method to obtain single crystals beneficial to their research.


Assuntos
Álcool Desidrogenase/química , Cobalto/química , Complexos de Coordenação/química , Fígado/enzimologia , Modelos Químicos , Cristalografia por Raios X , Imidazóis , Ligantes , Nitrogênio/química , Espectrometria de Massas por Ionização por Electrospray , Enxofre/química , Zinco/química
13.
Anal Chim Acta ; 1113: 18-25, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32340665

RESUMO

Magnetic trapping has been employed in the development of analytical methods owing to its ease and simplicity in handling samples. Nevertheless, the generation of functional probes is usually time consuming. A new and simple affinity method that uses gadolinium ion (Gd3+), a magnetic ion, as affinity probe for magnetic tapping of pathogenic bacteria was demonstrated in the present study. Escherichia coli O157:H7, Staphylococcus aureus, and Acinetobacter baumannii were selected as model bacteria. The model bacteria were magnetically isolated after incubation in Tris buffer (pH 8) containing Gd3+ (0.1 M) under microwave heating (power: 180 W, 90 s × 3). The resultant Gd3+-bacterium conjugates possessed sufficient magnetism, resulting in magnetic aggregations by an external magnet (∼4,000 Gauss). For ease of magnetic isolation, the sample containing Gd3+-bacterium complexes was stirred by a small magnet. After 1 h, the magnet attached with precipitates, i.e., Gd3+-bacterium conjugates, was readily removed using a pair of tweezers. The bacteria in the resultant conjugates were characterized by matrix-assisted laser desorption/ionization mass spectrometry. The limits of detection of the current approach toward E. coli O157:H7, S. aureus, and A. baumannii in complex samples were ∼104-105 cells mL-1.


Assuntos
Acinetobacter baumannii/isolamento & purificação , Técnicas Bacteriológicas/métodos , Escherichia coli O157/isolamento & purificação , Gadolínio/química , Staphylococcus aureus/isolamento & purificação , Acinetobacter baumannii/química , Animais , Sangue/microbiologia , Bovinos , Complexos de Coordenação/química , Difosfatos/química , Escherichia coli O157/química , Limite de Detecção , Fenômenos Magnéticos , Microbiologia do Solo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Staphylococcus aureus/química
14.
Inorg Chem ; 59(8): 5728-5741, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32242663

RESUMO

[44/47Sc]Sc3+, [68Ga]Ga3+, and [111In]In3+ are the three most attractive trivalent smaller radiometalnuclides, offering a wide range of distinct properties (emission energies and types) in the toolbox of nuclear medicine. In this study, all three of the metal ions are successfully chelated using a new oxine-based hexadentate ligand, H3glyox, which forms thermodynamically stable neutral complexes with exceptionally high pM values [pIn (34) > pSc (26) > pGa (24.9)]. X-ray diffraction single crystal structures with stable isotopes revealed that the ligand is highly preorganized and has a perfect fit to size cavity to form [Sc(glyox)(H2O)] and [In(glyox)(H2O)] complexes. Quantitative radiolabeling with gallium-68 (RCY > 95%, [L] = 10-5 M) and indium-111 (RCY > 99%, [L] = 10-8 M) was achieved under ambient conditions (RT, pH 7, and 15 min) with very high apparent molar activities of 750 MBq/µmol and 650 MBq/nmol, respectively. Preliminary quantitative radiolabeling of [44Sc]ScCl3 (RCY > 99%, [L] = 10-6 M) was fast at room temperature (pH 7 and 10 min). In vitro experiments revealed exceptional stability of both [68Ga]Ga(glyox) and [111In]In(glyox) complexes against human serum (transchelation <2%) and its suitability for biological applications. Additionally, on chelation with metal ions, H3glyox exhibits enhanced fluorescence, which was employed to determine the stability constants for Sc(glyox) in addition to the in-batch UV-vis spectrophotometric titrations; as a proof-of-concept these complexes were used to obtain fluorescence images of live HeLa cells using Sc(glyox) and Ga(glyox), confirming the viability of the cells. These initial investigations suggest H3glyox to be a valuable chelator for radiometal-based diagnosis (nuclear and optical imaging) and therapy.


Assuntos
Quelantes/farmacologia , Complexos de Coordenação/farmacologia , Corantes Fluorescentes/farmacologia , Oximas/farmacologia , Compostos Radiofarmacêuticos/farmacologia , Quelantes/síntese química , Complexos de Coordenação/sangue , Complexos de Coordenação/química , Estabilidade de Medicamentos , Corantes Fluorescentes/química , Radioisótopos de Gálio/química , Células HeLa , Humanos , Radioisótopos de Índio/química , Marcação por Isótopo , Ligantes , Microscopia de Fluorescência/métodos , Oximas/síntese química , Estudo de Prova de Conceito , Radioisótopos/química , Compostos Radiofarmacêuticos/sangue , Compostos Radiofarmacêuticos/química , Escândio/química , Termodinâmica
15.
Chemistry ; 26(41): 8875-8878, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32237247

RESUMO

The nickel(II)-mediated self-assembly of a multimeric DNA binder is described. The binder is composed of two metal-chelating peptides derived from a bZIP transcription factor (brHis2 ) and one short AT-hook domain equipped with two bipyridine ligands (HkBpy2 ). These peptides reversibly assemble in the presence of NiII ions at selected DNA sequences of 13 base pairs.


Assuntos
Complexos de Coordenação/química , DNA/química , Níquel/química , Peptídeos/química , Fatores de Transcrição/química , Complexos de Coordenação/síntese química , Íons/química , Ligantes
16.
Chemistry ; 26(34): 7657-7671, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32297355

RESUMO

A series of homoleptic and heteroleptic bismuth(III) flavonolate complexes derived from six flavonols of varying substitution have been synthesised and structurally characterised. The complexes were evaluated for antibacterial activity towards several problematic Gram-positive (Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE)) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. The cell viability of COS-7 (monkey kidney) cells treated with the bismuth flavonolates was also studied to determine the effect of the complexes on mammalian cells. The heteroleptic complexes [BiPh(L)2 ] (in which L=flavonolate) showed good antibacterial activity towards all of the bacteria but reduced COS-7 cell viability in a concentration-dependent manner. The homoleptic complexes [Bi(L)3 ] exhibited activity towards the Gram-positive bacteria and showed low toxicity towards the mammalian cell line. Bismuth uptake studies in VRE and COS-7 cells treated with the bismuth flavonolate complexes indicated that Bi accumulation is influenced by both the substitution of the flavonolate ligands and the degree of substitution at the bismuth centre.


Assuntos
Antibacterianos/farmacologia , Bismuto/química , Complexos de Coordenação/química , Escherichia coli/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/química , Escherichia coli/química , Bactérias Gram-Positivas/química , Humanos , Staphylococcus aureus Resistente à Meticilina/química , Pseudomonas aeruginosa/química , Staphylococcus aureus/química
17.
Chemistry ; 26(34): 7595-7601, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32302020

RESUMO

We propose post-metalation modification as a useful strategy to control the guest recognition behavior of a metal-containing macrocyclic host. This is based on the ligand exchange of the axial ligands of a cobalt(III) dinuclear macrocyclic host, [LCo2 X4 ]2+ (X=axial amine ligand). Four piperidine ligands in [LCo2 (pip)4 ]2+ (pip=piperidine) were site-selectively replaced with primary amines. The competitive experiments revealed that the order of the affinity toward the cobalt centers in [LCo2 X4 ]2+ is primary amine > secondary amine > tertiary amine and that the piperidine-coordinating complex, [LCo2 (pip)4 ]2+ , was reasonably reactive among the isolable complexes. Indeed, two piperidine ligands at the diagonal positions in [LCo2 (pip)4 ]2+ were site-selectively replaced with pyridine or acetate ion. The replacement of piperidine with acetate ion significantly enhanced the recognition ability towards Na+ .


Assuntos
Aminas/química , Cobalto/química , Complexos de Coordenação/química , Piridinas/química , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Ligantes , Metais , Estrutura Molecular
18.
PLoS One ; 15(4): e0231147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32287324

RESUMO

This paper reports the synthesis, characterization, anticancer screening and quantum chemical calculation of a tetradentate Schiff base 2,2'-((1E,1'E)-((2,2-dimethylpropane-1,3-diyl)bis- (azanylylidene))bis(methanylylidene))bis(4-fluorophenol) (L2F) and its Pd (II) complex (PdL2F). The compounds were characterized via UV-Visible, NMR, IR spectroscopy and single crystal x-ray diffraction. Density Functional Theory (DFT) and time-dependent DFT calculations in gas and solvent phases were carried out using B3LYP, B3P86, CAM-B3LYP and PBE0 hybrid functionals combined with LanL2DZ basis set. Complexation of L2F to form PdL2F was observed to cause a bathochromic shift of the maximum absorption bands of n-π* from 327 to 410 nm; an upfield shift for δ (HC = N) from 8.30 to 7.96 ppm and a decreased wavenumber for ν(C = N) from 1637 to 1616 cm-1. Overall, the UV-Vis, NMR and IR spectral data are relatively well reproduced through DFT and TD-DFT methods. L2F and PdL2F showed IC50 of 90.00 and 4.10 µg/mL, respectively, against human colorectal carcinoma (HCT116) cell lines, signifying increased anticancer activity upon complexation with Pd (II).


Assuntos
Complexos de Coordenação/farmacologia , Paládio/farmacologia , Bases de Schiff/farmacologia , Técnicas de Química Sintética/métodos , Complexos de Coordenação/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Concentração Inibidora 50 , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Paládio/química , Bases de Schiff/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Chem Pharm Bull (Tokyo) ; 68(3): 292-297, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115537

RESUMO

In this study, the adsorption capability of phosphate ion using a novel tri-metals complex hydroxide was evaluated for preventing the eutrophication in water environment. A nickel-aluminum-zirconium complex hydroxide (NAZ) was synthesized using each inorganic sulfate mixing ratio of 0.9 : 1.0 : 0.1 and was calcined at different temperatures. The characteristics of the NAZ were analyzed by scanning electron microscopy images, X-ray diffraction analysis, elemental distribution, and binding energy. Moreover, the amount adsorbed of phosphate ion onto uncalcined and calcined NAZ was measured. That of phosphate ions onto the uncalcined was the largest of all. These results suggested that the adsorption of phosphate ions tends to depend on the physicochemical properties (e.g., amount of hydroxyl groups, pore volumes, and pH) of the adsorbents. Moreover, the adsorption mechanism of phosphate ions was evaluated on the basis of binding energy and elemental analysis. After adsorption, the binding energy of phosphorus P (2s and 2p) peaked and the sulfur peak intensity S(2s) reduced. This result indicated that the adsorption mechanism of phosphate would be exchanged with sulfate ions.


Assuntos
Alumínio/química , Complexos de Coordenação/química , Hidróxidos/química , Níquel/química , Fosfatos/química , Zircônio/química , Adsorção , Complexos de Coordenação/síntese química , Tamanho da Partícula , Propriedades de Superfície
20.
Top Curr Chem (Cham) ; 378(2): 30, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32124072

RESUMO

The non-covalent assemblies among multiple non-identical metal complexes have scopes to develop a new subject area. There are infinite numbers of ways for different combinations among inorganic neutral or ionic complexes. Each partnering species of those molecular complexes would also have diversities by changing metal ions, ligands, oxidation states of metal ions, and coordination numbers. Keeping a view of the emergence of framework materials and self-assembled nano-structures of metal complexes, the non-covalently linked assemblies of inorganic molecular complexes would have scopes for new nano-dimensional materials. This account provides a systematic description of the different inorganic molecular complexes for a concerted effort to develop a new area that would have importance in applied materials.


Assuntos
Complexos de Coordenação/química , Compostos Inorgânicos/química , Ligantes , Metais/química , Conformação Molecular
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