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1.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443620

RESUMO

G-quadruplexes (G4s) are higher-order supramolecular structures, biologically important in the regulation of many key processes. Among all, the recent discoveries relating to RNA-G4s, including their potential involvement as antiviral targets against COVID-19, have triggered the ever-increasing need to develop selective molecules able to interact with parallel G4s. Naphthalene diimides (NDIs) are widely exploited as G4 ligands, being able to induce and strongly stabilize these structures. Sometimes, a reversible NDI-G4 interaction is also associated with an irreversible one, due to the cleavage and/or modification of G4s by functional-NDIs. This is the case of NDI-Cu-DETA, a copper(II) complex able to cleave G4s in the closest proximity to the target binding site. Herein, we present two original Cu(II)-NDI complexes, inspired by NDI-Cu-DETA, differently functionalized with 2-(2-aminoethoxy)ethanol side-chains, to selectively drive redox-catalyzed activity towards parallel G4s. The selective interaction toward parallel G4 topology, controlled by the presence of 2-(2-aminoethoxy)ethanol side chains, was already firmly demonstrated by us using core-extended NDIs. In the present study, the presence of protonable moieties and the copper(II) cavity, increases the binding affinity and specificity of these two NDIs for a telomeric RNA-G4. Once defined the copper coordination relationship and binding constants by competition titrations, ability in G4 stabilization, and ROS-induced cleavage were analyzed. The propensity in the stabilization of parallel topology was highlighted for both of the new compounds HP2Cu and PE2Cu. The results obtained are particularly promising, paving the way for the development of new selective functional ligands for binding and destructuring parallel G4s.


Assuntos
Complexos de Coordenação/química , Cobre/química , Quadruplex G , Imidas/química , Naftalenos/química , Sítios de Ligação , DEET/química , Ligantes , Oxirredução , Polietilenoglicóis/química , Relação Estrutura-Atividade
2.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361760

RESUMO

Self-assembly is the most powerful force for creating ordered supramolecular architectures from simple components under mild conditions. π···π stacking interactions have been widely explored in modern supramolecular chemistry as an attractive reversible noncovalent tool for the nondestructive fabrication of materials for different applications. Here, we report on the self-assembly of cytidine 5'-monophosphate (CMP) nucleotide and copper metal ions for the preparation of a rare nanoporous supramolecular metal-organic framework in water. π···π stacking interactions involving the aromatic groups of the ancillary 2,2'-bipyridine (bipy) ligands drive the self-assemblies of hexameric pseudo-amphiphilic [Cu6(bipy)6(CMP)2(µ-O)Br4]2+ units. Owing to the supramolecular geometric matching between the aromatic tails, a nanoporous crystalline phase with hydrophobic and hydrophilic chiral pores of 1.2 and 0.8 nanometers, respectively, was successfully synthesized. The encoded chiral information, contained on the enantiopure building blocks, is transferred to the final supramolecular structure, assembled in the very unusual topology 8T6. These kinds of materials, owing to chiral channels with chiral active sites from ribose moieties, where the enantioselective recognition can occur, are, in principle, good candidates to carry out efficient separation of enantiomers, better than traditional inorganic and organic porous materials.


Assuntos
2,2'-Dipiridil/química , Cobre/química , Citidina Monofosfato/química , Estruturas Metalorgânicas/síntese química , Cristalização , Cristalografia por Raios X , Interações Hidrofóbicas e Hidrofílicas , Estruturas Metalorgânicas/química , Estrutura Molecular , Porosidade , Soluções , Estereoisomerismo
3.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443319

RESUMO

Metformin has been used for decades in millions of type 2 diabetes mellitus patients. In this time, correlations between metformin use and the occurrence of other disorders have been noted, as well as unpredictable metformin side effects. Diabetes is a significant cancer risk factor, but unexpectedly, metformin-treated diabetic patients have lower cancer incidence. Here, we show that metformin forms stable complexes with copper (II) ions. Both copper(I)/metformin and copper(II)/metformin complexes form adducts with glutathione, the main intracellular antioxidative peptide, found at high levels in cancer cells. Metformin reduces cell number and viability in SW1222 and K562 cells, as well as in K562-200 multidrug-resistant cells. Notably, the antiproliferative effect of metformin is enhanced in the presence of copper ions.


Assuntos
Complexos de Coordenação/química , Cobre/química , Metformina/química , Sobrevivência Celular/efeitos dos fármacos , Glutationa/química , Humanos , Células K562 , Metformina/farmacologia
4.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445313

RESUMO

High levels of hyaluronic acid (HA) in tumors correlate with poor outcomes with several types of cancers due to HA-driven support of adhesion, migration and proliferation of cells. In this study we explored how to enhance the degradation of HA into low-molecular fragments, which cannot prevent the immune system to fight tumor proliferation and metastases. The physiological solution of HA was exposed to oxidative degradation by ascorbate and cupric ions in the presence of either one of three ortho isomeric Mn(III) substituted N-alkyl- and alkoxyalkylpyridylporphyrins or para isomeric Mn(III) N-methylpyridyl analog, commonly known as mimics of superoxide dismutase. The changes in hyaluronan degradation kinetics by four Mn(III) porphyrins were monitored by measuring the alteration in the dynamic viscosity of the HA solution. The ortho compounds MnTE-2-PyP5+ (BMX-010, AEOL10113), MnTnBuOE-2-PyP5+ (BMX-001) and MnTnHex-2-PyP5+ are able to redox cycle with ascorbate whereby producing H2O2 which is subsequently coupled with Cu(I) to produce the •OH radical essential for HA degradation. Conversely, with the para analog, MnTM-4-PyP5+, no catalysis of HA degradation was demonstrated, due to its inertness towards redox cycling with ascorbate. The impact of different Mn(III)-porphyrins on the HA decay was further clarified by electron paramagnetic resonance spectrometry. The ability to catalyze the degradation of HA in a biological milieu, in the presence of cupric ions and ascorbate under the conditions of high tumor oxidative stress provides further insight into the anticancer potential of redox-active ortho isomeric Mn(III) porphyrins.


Assuntos
Ácido Ascórbico/química , Ácido Hialurônico/química , Metaloporfirinas/química , Cobre/química , Magnésio/química , Oxirredução , Superóxido Dismutase/metabolismo
5.
ACS Appl Mater Interfaces ; 13(33): 38959-38968, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34379404

RESUMO

Chemotherapy continues to be the most commonly applied strategy for cancer. Despite the impressive clinical success obtained with several drugs, increasing numbers of (multi)drug-resistant tumors are reported. To overcome this shortcoming, novel drug candidates and delivery systems are urgently needed. Herein, a therapeutic copper polypyridine complex encapsulated in natural nanocarrier apoferritin is reported. The generated nanoparticles showed higher cytotoxicity toward various (drug-resistant) cancer cell lines than noncancerous cells. The study of the mechanism revealed that the compound triggers cell autophagy-dependent apoptosis. Promisingly, upon injection of the nanodrug conjugate into the bloodstream of a mouse model bearing a multidrug-resistant colon tumor, a strong tumor growth inhibition effect was observed. To date, this is the first study describing the encapsulation of a copper complex in apoferritin that acts by autophagy-dependent apoptosis.


Assuntos
Antineoplásicos/química , Apoferritinas/química , Neoplasias do Colo/tratamento farmacológico , Complexos de Coordenação/química , Cobre/química , Nanocápsulas/química , Animais , Antineoplásicos/farmacologia , Apoferritinas/metabolismo , Morte Celular Autofágica/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Complexos de Coordenação/farmacologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais
6.
ACS Appl Mater Interfaces ; 13(33): 39066-39075, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387079

RESUMO

A controlled release formulation based on silica microcapsules is an ideal selection to improve both the effective utilization and duration of pesticides to decrease ecological damage. Herein, a simple and green method for preparing double-shelled microcapsules was developed using a newly prepared quaternary ammonium ionic liquid (IL) as the functional additive to entrap avermectin (Ave) in mesoporous silica nanospheres (MSNs) and tannic acid-Cu (TA-Cu) complex as the sealing agent to form the core-shell structure (Ave-IL@MSN@TA-Cu). The obtained microcapsules with an average size of 538 nm had pH-responsive release property and good stability in soil. The half-life of microcapsules (34.66 days) was 3 times that of Ave emulsifiable concentrate (EC) (11.55 days) in a test soil, which illustrated that microcapsules could protect Ave from rapid degradation by microorganisms by releasing TA, copper, and quaternary ammonium in the soil. Ave-IL@MSN@TA-Cu microcapsules had better nematicidal activity and antibacterial activity than Ave EC due to the synergistic effect of Ave, IL, and copper incorporated in the microcapsules. Pot experiments showed that the control efficacy of microcapsules was 87.10% against Meloidogyne incognita, which is better than that of Ave EC (41.94%) at the concentration of 1.0 mg/plant by the root-irrigation method after 60 days of treatment owing to the extended duration of Ave in microcapsules. The simple and green method for the preparation of double-shelled microcapsules based on natural quaternary ammonium IL would have tremendous potential for the extensive development of controlled release pesticide formulations.


Assuntos
Cápsulas/química , Preparações de Ação Retardada/química , Controle de Pragas/métodos , Praguicidas/química , Dióxido de Silício/química , Tylenchoidea/efeitos dos fármacos , Animais , Complexos de Coordenação/química , Cobre/química , Preparações de Ação Retardada/farmacologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Química Verde , Concentração de Íons de Hidrogênio , Líquidos Iônicos/química , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/farmacologia , Praguicidas/farmacologia , Porosidade , Compostos de Amônio Quaternário/química , Solubilidade , Taninos/química , Fatores de Tempo
7.
ACS Appl Mater Interfaces ; 13(33): 39854-39867, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387478

RESUMO

Despite the growing research on biomolecule-inorganic nanoflowers for multiple applications, it remains challenging to control their development on stationary platforms for potential portable and wearable devices. In this work, the self-assembly of Cu3(PO4)2-bovine serum albumin hybrid nanoflowers is facilitated by an alumina platform whose surface is tailored by wet plasma electrolysis. This allows an interlocking of hybrid nanoflowers with the surface motifs of the solid platform, resulting in a hierarchy similar to nanocarnation (NC) petals on an inorganic bed. Density functional theory calculations are performed to reveal the primary bonding mode between the organic and inorganic components and to identify the active sites of the protein structure in order to provide mechanistic insights that can explain self-assembly of NCs overall. The hybrid architecture displays an adaptive microstructure in different aqueous environment, giving rise to a dual-function based on its electrochemical stability and catalytic activity toward radical degradation of organic pollutant.


Assuntos
Corantes/química , Cobre/química , Nanopartículas/química , Fosfatos/química , Soroalbumina Bovina/química , Poluentes Químicos da Água/química , Catálise , Teoria da Densidade Funcional , Técnicas Eletroquímicas , Peróxido de Hidrogênio/química , Modelos Moleculares , Oxirredução , Agregados Proteicos , Propriedades de Superfície
8.
Inorg Chem ; 60(14): 10186-10198, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34232628

RESUMO

An original example of modular crystal engineering involving molecular magnetic {CuII[WV(CN)8]}- bilayers and adeninium cations (AdeH+) toward the new layered molecular magnet (AdeH){CuII[WV(CN)8]}·2H2O (1) is presented. 1 crystallizes within the monoclinic C2 space group (a = 41.3174(12), b = 7.0727(3), c = 7.3180(2) Å, ß = 93.119(3)°, and V = 2135 Å3). The bilayer topology is based on a stereochemical matching between the square pyramidal shape of CuII moiety and the bicapped trigonal prismatic shape of [WV(µ-CN)5(CN)3], and the separation between bilayers is significantly increased (by ∼50%; from ca. 9.5 to ca. 14.5 Å) compared to several former analogues in this family. This was achieved via a unique combination of (i) a 1D ribbonlike hydrogen bond system {AdeH+···H2O···AdeH+···}∞ exploiting planar water-assisted Hoogsteen···Sugar synthons with (ii) parallel 1D π-π stacks {AdeH+···AdeH+}∞. In-plane 2D XY magnetism is characterized by a Tc close to 33 K, Hc,in-plane = 60 Oe, and Hc,out-of-plane = 750 Oe, high values of in-plane γ critical exponents (γb = 2.34(6) for H||b and γc = 2.16(5) for H||c), and a Berezinskii-Kosterlitz-Thouless (BKT) topological phase transition, deduced from crystal-orientation-dependent scaling analysis. The obtained values of in-plane ν critical exponents, νb = 0.48(5) for H||b and νc = 0.49(3) for H||c, confirm the BKT transition (νBKT = 0.5). Full-range angle-resolved monocrystalline magnetic measurements supported by dedicated calculations indicated the occurrence of nonlinear susceptibility performance within the easy plane in a magnetically ordered state. We refer the occurrence of this phenomenon to spontaneous resolution in the C2 space group, a tandem not observed in studies on previous analogues and rarely reported in the field of molecular materials. The above magneto-supramolecular strategy may provide a novel means for the design of 2D molecular magnetic networks and help to uncover the inherent phenomena.


Assuntos
Adenina/química , Fenômenos Magnéticos , Compostos Organometálicos/química , Cobre/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
9.
Inorg Chem ; 60(15): 11530-11547, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34279088

RESUMO

The Cu2+ complexes formed by a series of cyclen derivatives bearing sulfur pendant arms, 1,4,7,10-tetrakis[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (DO4S), 1,4,7-tris[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (DO3S), 1,4,7-tris[2-(methylsulfanyl)ethyl]-10-acetamido-1,4,7,10-tetraazacyclododecane (DO3SAm), and 1,7-bis[2-(methylsulfanyl)ethyl]-4,10-diacetic acid-1,4,7,10-tetraazacyclododecane (DO2A2S), were studied in aqueous solution at 25 °C from thermodynamic and structural points of view to evaluate their potential as chelators for copper radioisotopes. UV-vis spectrophotometric out-of-cell titrations under strongly acidic conditions, direct in-cell UV-vis titrations, potentiometric measurements at pH >4, and spectrophotometric Ag+-Cu2+ competition experiments were performed to evaluate the stoichiometry and stability constants of the Cu2+ complexes. A highly stable 1:1 metal-to-ligand complex (CuL) was found in solution at all pH values for all chelators, and for DO2A2S, protonated species were also detected under acidic conditions. The structures of the Cu2+ complexes in aqueous solution were investigated by UV-vis and electron paramagnetic resonance (EPR), and the results were supported by relativistic density functional theory (DFT) calculations. Isomers were detected that differed from their coordination modes. Crystals of [Cu(DO4S)(NO3)]·NO3 and [Cu(DO2A2S)] suitable for X-ray diffraction were obtained. Cyclic voltammetry (CV) experiments highlighted the remarkable stability of the copper complexes with reference to dissociation upon reduction from Cu2+ to Cu+ on the CV time scale. The Cu+ complexes were generated in situ by electrolysis and examined by NMR spectroscopy. DFT calculations gave further structural insights. These results demonstrate that the investigated sulfur-containing chelators are promising candidates for application in copper-based radiopharmaceuticals. In this connection, the high stability of both Cu2+ and Cu+ complexes can represent a key parameter for avoiding in vivo demetalation after bioinduced reduction to Cu+, often observed for other well-known chelators that can stabilize only Cu2+.


Assuntos
Complexos de Coordenação/química , Radioisótopos de Cobre/análise , Cobre/química , Ciclamos/química , Enxofre/química , Radioisótopos de Cobre/química , Teoria da Densidade Funcional , Modelos Moleculares , Conformação Molecular , Oxirredução
10.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279368

RESUMO

The purpose of this study was to identify new metal-based anticancer drugs; to this end, we synthesized two new copper(II) complexes, namely [Cu(ncba)4(phen)] (1) and [Cu(ncba)4(bpy)] (2), comprised 4-chloro-3-nitrobenzoic acid as the main ligand. The single-crystal XRD approach was employed to determine the copper(II) complex structures. Binding between these complexes and calf thymus DNA (CT-DNA) and human serum albumin (HSA) was explored by electronic absorption, fluorescence spectroscopy, and viscometry. Both complexes intercalatively bound CT-DNA and statically and spontaneously quenched DNA/HSA fluorescence. A CCK-8 assay revealed that complex 1 and complex 2 had substantial antiproliferative influences against human cancer cell lines. Moreover, complex 1 had greater antitumor efficacy than the positive control cisplatin. Flow cytometry assessment of the cell cycle demonstrated that these complexes arrested the HepG2 cell cycle and caused the accumulation of G0/G1-phase cells. The mechanism of cell death was elucidated by flow cytometry-based apoptosis assays. Western blotting revealed that both copper(II) complexes induced apoptosis by regulating the expression of the Bcl-2(Bcl-2, B cell lymphoma 2) protein family.


Assuntos
Antineoplásicos/síntese química , Clorobenzoatos/química , Complexos de Coordenação/síntese química , Cobre/química , Albumina Sérica Humana/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/farmacologia , DNA/química , Células Hep G2 , Humanos
11.
J Photochem Photobiol B ; 221: 112249, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34237541

RESUMO

Increasing interests in photodynamic treatment (PDT) for food preservation require a holistic method to evaluate and compare different photosensitizer (PS)-light treatments. In this report, the absorbed photons were used as the basis to assess the antimicrobial photodynamic efficacy of two PSs, chlorophyllin sodium magnesium salt (Chl-Mg) and chlorophyllin sodium copper salt (Chl-Cu), under blue and white light against two typical foodborne pathogens, Gram-negative Escherichia coli, and Gram-positive Staphylococcus aureus. The results showed that the phototoxicity of a PS was predominantly decided by the absorbed photons rather than the characteristics of light sources. Photosensitized Chl-Mg exhibited superior antimicrobial activity as compared to that of ChlCu. The applied treatments were found to be more effective against S. aureus than E. coli. Bacterial inactivation kinetics as a function of the number of absorbed photons could be described by Weibull model with R2 from 0.947-0.962, and kinetics constants D in the range of 0.202 × 1017 photons/cm2-2.409 × 1018 photons/cm2. The kinetics models may find promising applications in the design, assessment, and optimization of PDT processes.


Assuntos
Escherichia coli/efeitos dos fármacos , Luz , Fármacos Fotossensibilizantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Clorofilídeos/química , Cobre/química , Escherichia coli/efeitos da radiação , Microbiologia de Alimentos , Magnésio/química , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo , Sódio/química , Staphylococcus aureus/efeitos da radiação
12.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34210014

RESUMO

Human serum transferrin (HST) is a glycoprotein involved in iron transport that may be a candidate for functionalized nanoparticles to bind and target cancer cells. In this study, the effects of the simple and doped with cobalt (Co) and copper (Cu) ferrihydrite nanoparticles (Fh-NPs, Cu-Fh-NPs, and Co-Fh-NPs) were studied by spectroscopic and molecular approaches. Fluorescence spectroscopy revealed a static quenching mechanism for all three types of Fh-NPs. All Fh-NPs interacted with HST with low affinity, and the binding was driven by hydrogen bonding and van der Waals forces for simple Fh-NPs and by hydrophobic interactions for Cu-Fh-NPs and Co-Fh-NPs binding, respectively. Of all samples, simple Fh-NPs bound the most to the HST binding site. Fluorescence resonance energy transfer (FRET) allowed the efficient determination of the energy transfer between HST and NPs and the distance at which the transfer takes place and confirmed the mechanism of quenching. The denaturation of the HST is an endothermic process, both in the case of apo HST and HST in the presence of the three types of Fh-NPs. Molecular docking studies revealed that Fh binds with a low affinity to HST (Ka = 9.17 × 103 M-1) in accord with the fluorescence results, where the interaction between simple Fh-NPs and HST was described by a binding constant of 9.54 × 103 M-1.


Assuntos
Cobalto/química , Compostos Férricos/síntese química , Transferrina/química , Transferrina/metabolismo , Cobre/química , Compostos Férricos/química , Transferência Ressonante de Energia de Fluorescência , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Simulação de Acoplamento Molecular , Nanopartículas , Ligação Proteica , Conformação Proteica , Espectrometria de Fluorescência , Termodinâmica
13.
Int J Mol Sci ; 22(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205682

RESUMO

In this paper, we present findings from studying the interaction of copper(II) ions with the His2-cyclopentapeptide and the role of proline used for the purpose of potentiometric titration and UV-Vis, CD and EPR spectroscopic measurements. Experiments of two homodetic peptides differing by one amino acid residue were conducted for a ligand to metal ratio of 1:1 in the pH range 2.5-11.0. The presented studies reveal that peptides form only mononuclear complexes, and the CuH2L complex appears in the system first (for both L1 and L2). Study results show that the presence of Pro influences the structure of formed complexes and their stabilities and has a strong impact on the efficiency of copper(II) coordination.


Assuntos
Cobre/química , Peptídeos Cíclicos/química , Prolina/química
14.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204328

RESUMO

The use of experimental relations to approximate the efficient thermophysical properties of a nanofluid (NF) with Cu nanoparticles (NPs) and hybrid nanofluid (HNF) with Cu-SWCNT NPs and subsequently model the two-dimensional pulsatile Casson fluid flow under the impact of the magnetic field and thermal radiation is a novelty of the current study. Heat and mass transfer analysis of the pulsatile flow of non-Newtonian Casson HNF via a Darcy-Forchheimer porous channel with compliant walls is presented. Such a problem offers a prospective model to study the blood flow via stenosed arteries. A finite-difference flow solver is used to numerically solve the system obtained using the vorticity stream function formulation on the time-dependent governing equations. The behavior of Cu-based NF and Cu-SWCNT-based HNF on the wall shear stress (WSS), velocity, temperature, and concentration profiles are analyzed graphically. The influence of the Casson parameter, radiation parameter, Hartmann number, Darcy number, Soret number, Reynolds number, Strouhal number, and Peclet number on the flow profiles are analyzed. Furthermore, the influence of the flow parameters on the non-dimensional numbers such as the skin friction coefficient, Nusselt number, and Sherwood number is also discussed. These quantities escalate as the Reynolds number is enhanced and reduce by escalating the porosity parameter. The Peclet number shows a high impact on the microorganism's density in a blood NF. The HNF has been shown to have superior thermal properties to the traditional one. These results could help in devising hydraulic treatments for blood flow in highly stenosed arteries, biomechanical system design, and industrial plants in which flow pulsation is essential.


Assuntos
Cobre , Hemodinâmica , Hidrodinâmica , Nanopartículas Metálicas , Modelos Cardiovasculares , Fluxo Pulsátil , Algoritmos , Artérias/patologia , Artérias/fisiopatologia , Circulação Sanguínea , Constrição Patológica , Cobre/química , Humanos , Nanopartículas Metálicas/química , Porosidade , Suspensões
15.
Int J Nanomedicine ; 16: 4559-4577, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267513

RESUMO

Purpose: Reactive oxygen species (ROS) are a group of signaling biomolecules that play important roles in the cell cycle. When intracellular ROS homeostasis is disrupted, it can induce cellular necrosis and apoptosis. It is desirable to effectively cascade-amplifying ROS generation and weaken antioxidant defense for disrupting ROS homeostasis in tumor microenvironment (TME), which has been recognized as a novel and ideal antitumor strategy. Multifunctional nanozymes are highly promising agents for ROS-mediated therapy. Methods: This study constructed a novel theranostic nanoagent based on PEG@Cu2-xS@Ce6 nanozymes (PCCNs) through a facile one-step hydrothermal method. We systematically investigated the photodynamic therapy (PDT)/photothermal therapy (PTT) properties, catalytic therapy (CTT) and glutathione (GSH) depletion activities of PCCNs, antitumor efficacy induced by PCCNs in vitro and in vivo. Results: PCCNs generate singlet oxygen (1O2) with laser (660 nm) irradiation and use catalytic reactions to produce hydroxyl radical (•OH). Moreover, PCCNs show the high photothermal performance under NIR II 1064-nm laser irradiation, which can enhance CTT/PDT efficiencies to increase ROS generation. The properties of O2 evolution and GSH consumption of PCCNs achieve hypoxia-relieved PDT and destroy cellular antioxidant defense system respectively. The excellent antitumor efficacy in 4T1 tumor-bearing mice of PCCNs is achieved through disrupting ROS homeostasis-involved therapy under the guidance of photothermal/photoacoustic imaging. Conclusion: Our study provides a proof of concept of "all-in-one" nanozymes to eliminate tumors via disrupting ROS homeostasis.


Assuntos
Homeostase/efeitos dos fármacos , Hipertermia Induzida/métodos , Raios Infravermelhos , Nanomedicina/métodos , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Animais , Catálise , Linhagem Celular Tumoral , Cério/química , Cobre/química , Glutationa/metabolismo , Humanos , Camundongos , Polietilenoglicóis/química , Sulfetos/química
16.
Ecotoxicol Environ Saf ; 221: 112456, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34198187

RESUMO

Biochar-derived water-extractable organic matter (WEOM) was obtained under low-temperature pyrolysis (300 °C) using corncob as raw material. WEOM may affect the mobility and bioavailability of soil heavy metals (HMs) through complexation when biochar was used for soil HM remediation. Herein, the characteristics of complexation between HMs (Cr(III) and Cu(II)) and biochar-derived WEOM were investigated by using spectroscopic techniques in conjunction with parallel factor (PARAFAC) analysis and two-dimensional correlation spectroscopy (2D-COS). Six components were identified by PARAFAC modeling, in which protein-, fulvic- and humic-like components accounted for 48.86%, 25.63% and 25.51%, respectively. A nonlinear model was employed to determine the conditional stability constant (KM) and total ligand concentration (CL) of WEOM-HM complexes. The log KM values were in the range of 4.02-5.04 for WEOM-Cr(III) and 4.04-6.58 for WEOM-Cu(II). The 2D-COS in conjunction with log-transformed synchronous fluorescence spectroscopy (SFS) suggested that WEOM components were preferentially complexed with HMs in the following order: 433/270, 433/335, 496/270, 496/335, 370/335, 433/402, 496/402, 335/290, 402/290 for Cr(III), and 290/280, 390/280, 433/280, 496/280, 433/335, 496/335, 390/335, 433/420, 496/402, 335/290, 316/290 for Cu(II). The results of 2D-FTIR-COS suggested a preferential bonding of Cr(III) to the C-N group of alkyl, and Cu(II) to the CO group of alcohols, ethers and esters. Meanwhile, the CO group of ethers and the CN group of alkyl indicated preferential susceptibilities for the addition of Cr(III) and Cu(II) at different concentrations. In addition, protein-like components had remarkably higher total ligand concentration (CL) than fulvic- or humic-like components.


Assuntos
Carvão Vegetal/química , Cromo/química , Cobre/química , Benzopiranos/química , Substâncias Húmicas , Proteínas/química , Pirólise , Temperatura , Água/química , Zea mays
17.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199667

RESUMO

Nanoparticles (NPs) with a high atomic number (Z) are promising radiosensitizers for cancer therapy. However, the dependence of their efficacy on irradiation conditions is still unclear. In the present work, 11 different metal and metal oxide NPs (from Cu (ZCu = 29) to Bi2O3 (ZBi = 83)) were studied in terms of their ability to enhance the absorbed dose in combination with 237 X-ray spectra generated at a 30-300 kVp voltage using various filtration systems and anode materials. Among the studied high-Z NP materials, gold was the absolute leader by a dose enhancement factor (DEF; up to 2.51), while HfO2 and Ta2O5 were the most versatile because of the largest high-DEF region in coordinates U (voltage) and Eeff (effective energy). Several impacts of the X-ray spectral composition have been noted, as follows: (1) there are radiation sources that correspond to extremely low DEFs for all of the studied NPs, (2) NPs with a lower Z in some cases can equal or overcome by the DEF value the high-Z NPs, and (3) the change in the X-ray spectrum caused by a beam passing through the matter can significantly affect the DEF. All of these findings indicate the important role of carefully planning radiation exposure in the presence of high-Z NPs.


Assuntos
Cobre/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Neoplasias/radioterapia , Radiossensibilizantes/uso terapêutico , Bismuto/química , Bismuto/uso terapêutico , Cobre/química , Relação Dose-Resposta a Droga , Humanos , Nanopartículas Metálicas/química , Método de Monte Carlo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Óxidos/química , Óxidos/uso terapêutico , Radiossensibilizantes/química , Dosagem Radioterapêutica
18.
Inorg Chem ; 60(15): 11081-11089, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34242020

RESUMO

A CuI-TbIII heterometallic MOF, namely 1·DMF, was obtained via a coordination assembly process of isonicotinic acid with CuI and TbIII. 1·DMF can be switched to 1·MeOH in methanol with a luminescent emission response. Meanwhile, 1·MeOH exhibits a reversible single-crystal transformation to 1·DMF after immersion in DMF. Both MOFs have superior physicochemical stability. The 1·DMF-based biosensor has a remarkable sensing performance toward penicillin.


Assuntos
Cobre/química , Luminescência , Compostos Organometálicos/química , Penicilinas/análise , Térbio/química , Teoria da Densidade Funcional , Modelos Moleculares , Conformação Molecular , Penicilinas/química
19.
Inorg Chem ; 60(15): 11297-11319, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34279079

RESUMO

Three new thiosemicarbazones (TSCs) HL1-HL3 as triapine analogues bearing a redox-active phenolic moiety at the terminal nitrogen atom were prepared. Reactions of HL1-HL3 with CuCl2·2H2O in anoxic methanol afforded three copper(II) complexes, namely, Cu(HL1)Cl2 (1), [Cu(L2)Cl] (2'), and Cu(HL3)Cl2 (3), in good yields. Solution speciation studies revealed that the metal-free ligands are stable as HL1-HL3 at pH 7.4, while being air-sensitive in the basic pH range. In dimethyl sulfoxide they exist as a mixture of E and Z isomers. A mechanism of the E/Z isomerization with an inversion at the nitrogen atom of the Schiff base imine bond is proposed. The monocationic complexes [Cu(L1-3)]+ are the most abundant species in aqueous solutions at pH 7.4. Electrochemical and spectroelectrochemical studies of 1, 2', and 3 confirmed their redox activity in both the cathodic and the anodic region of potentials. The one-electron reduction was identified as metal-centered by electron paramagnetic resonance spectroelectrochemistry. An electrochemical oxidation pointed out the ligand-centered oxidation, while chemical oxidations of HL1 and HL2 as well as 1 and 2' afforded several two-electron and four-electron oxidation products, which were isolated and comprehensively characterized. Complexes 1 and 2' showed an antiproliferative activity in Colo205 and Colo320 cancer cell lines with half-maximal inhibitory concentration values in the low micromolar concentration range, while 3 with the most closely related ligand to triapine displayed the best selectivity for cancer cells versus normal fibroblast cells (MRC-5). HL1 and 1 in the presence of 1,4-dithiothreitol are as potent inhibitors of mR2 ribonucleotide reductase as triapine.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Cobre/química , Piridinas/química , Tiossemicarbazonas/química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Complexos de Coordenação/química , Eletroquímica , Humanos , Oxirredução , Soluções , Estereoisomerismo
20.
Nat Commun ; 12(1): 4065, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210971

RESUMO

Strategies that enable intermolecular site-selective C-H bond functionalisation of organic molecules provide one of the cornerstones of modern chemical synthesis. In chloroalkane synthesis, such methods for intermolecular site-selective aliphatic C-H bond chlorination have, however, remained conspicuously rare. Here, we present a copper(I)-catalysed synthetic method for the efficient site-selective C(sp3)-H bond chlorination of ketones, (E)-enones and alkylbenzenes by dichloramine-T at room temperature. A key feature of the broad substrate scope is tolerance to unsaturation, which would normally pose an immense challenge in chemoselective aliphatic C-H bond functionalisation. By unlocking dichloramine-T's potential as a chlorine radical atom source, the product site-selectivities achieved are among the most selective in alkane functionalisation and should find widespread utility in chemical synthesis. This is exemplified by the late-stage site-selective modification of a number of natural products and bioactive compounds, and gram-scale preparation and formal synthesis of two drug molecules.


Assuntos
Domínio Catalítico , Cobre/química , Cetonas/química , Sulfonamidas/química , Produtos Biológicos/química , Carbono/química , Catálise , Halogenação , Hidrogênio/química , Temperatura
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