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1.
ACS Appl Mater Interfaces ; 13(33): 39100-39111, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34382406

RESUMO

In this work, a nanoplatform (FeCORM NPs) loaded with an iron-carbonyl complex was constructed. By exploiting chemodynamic therapy (CDT) and immunogenic cell death (ICD)-induced immunotherapy (IMT), the nanoparticles exhibited excellent efficacy against lung metastasis of melanoma in vivo. The iron-carbonyl compound of the nanomaterials could be initiated by both glutathione (GSH) and hydrogen peroxide (H2O2) to release CO and generate ferrous iron through ligand exchange and oxidative destruction pathways. The released CO caused mitochondria damage, whereas the generated ferrous iron led to oxidative stress via the Fenton reaction. On the other hand, the nanomaterials induced ICD-based IMT, which worked jointly with CDT to exhibit excellent effects against lung metastasis of melanoma through a mouse model. This work demonstrated how a nanoplatform, simple and stable but showing excellent efficacy against tumors, could be built using simple building blocks via a self-assembling approach. Importantly, the system took advantage of relatively high levels of GSH and H2O2 in tumors to initiate the therapeutic effects, which rendered the nanoplatform with a capability to differentiate normal cells from tumor cells. In principle, the system has great potential for future clinical applications, not only in the treatment of lung metastasis of melanoma but also in suppressing other types of tumors.


Assuntos
Antineoplásicos/química , Monóxido de Carbono/química , Compostos de Ferro/química , Neoplasias Pulmonares/tratamento farmacológico , Melanoma/metabolismo , Nanopartículas Metálicas/química , Animais , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Monóxido de Carbono/farmacocinética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenvolvimento de Medicamentos , Feminino , Glutationa/química , Humanos , Peróxido de Hidrogênio/química , Imunoterapia/métodos , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Neoplasias Experimentais , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
2.
ACS Appl Mater Interfaces ; 13(33): 39126-39134, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34383476

RESUMO

The usage of exogenous antioxidant materials to relieve oxidative stress offers an important strategy for the therapy of oxidative stress-induced injuries. However, the fabrication processes toward the antioxidant materials usually require the involvement of extra metal ions and organic agents, as well as sophisticated purification steps, which might cause tremendous environmental stress and induce unpredictable side effects in vivo. To address these issues, herein, we proposed a novel strategy to fabricate green nanoparticles for efficiently modulating oxidative stress, which was facilely prepared from tea polyphenol extracts (originated from green tea) via a green enzymatic polymerization-based chemistry method. The resulting nanoparticles possessed a uniform spherical morphology and good stability in water and biomedium and demonstrated excellent radical scavenging properties. These nanoparticle scavengers could effectively prevent intracellular oxidative damage, accelerate wound recovery, and protect the kidneys from reactive oxygen species damaging in the acute kidney injury model. We hope this work will inspire the further development of more types of green nanoparticles for antioxidant therapies via similar synthetic strategies using green biomass materials.


Assuntos
Injúria Renal Aguda/prevenção & controle , Antioxidantes/química , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/química , Chá/química , Células 3T3 , Células A549 , Animais , Antioxidantes/farmacologia , Catecóis/química , Sobrevivência Celular/efeitos dos fármacos , Feminino , Sequestradores de Radicais Livres/metabolismo , Química Verde , Peroxidase do Rábano Silvestre/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica , Cicatrização/efeitos dos fármacos
3.
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
4.
ACS Appl Mater Interfaces ; 13(33): 39719-39729, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34392680

RESUMO

In this work, cucurbiturils (CBs), a class of macrocyclic supramolecules, were observed to have an interesting peroxidase-like activity, which is metal-free, substrate-specific, thermophilic, acidophilic, and insensitive to ionic strength. By coating CBs on enzyme-encapsulated zeolitic imidazolate framework-8 (ZIF-8), a composite nanozyme was constructed, which retains the catalytic ability of CBs and enzymes and makes them cascade. On addition of the substrate, i.e., the detection target, a highly efficient cascade catalysis can be launched in all the spatial directions to generate sensitive and visible signals. Convenient detection of glucose and cholesterol as models is thereby achieved. More importantly, we have also successfully constructed a composite nanozyme-based sensor array (6 × 8 wells) and thereby achieved simultaneous colorimetric analysis of multiple samples. The concept and successful practice of the construction of the unique core-shell supramolecule/biomolecule@nanomaterial architecture provide the possibility to fabricate next-generation multifunctional materials and create new applications by integrating their unique functions.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Nanocompostos/química , Peroxidases/química , Zeolitas/química , Técnicas Biossensoriais , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Catálise , Colorimetria , Corantes Fluorescentes/química , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/química , Imidazóis/metabolismo , Simulação de Acoplamento Molecular , Oxirredução , Peroxidases/metabolismo , Impressão Tridimensional
5.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208193

RESUMO

Metronidazole is a drug widely used in the prevention and treatment of bacterial infections. Due to its possibility of the formation of stable metal complexes, it was decided to broaden its activity spectrum by introducing the silver(I) coordination compounds i.e., [Ag(MTZ)2NO3] and [(Ag(MTZ)2)2]SO4, which have significant antibacterial properties. The paper presents a description of a new qualitative and quantitative analysis of metronidazole in bulk and possible pharmaceutical preparations by thin-layer chromatography with densitometric detection. Optimal separation conditions were selected, and the analytical procedure was validated according to the ICH guidelines. The obtained data indicate that the method is sufficiently sensitive, precise, and accurate. The stability of the metronidazole solutions obtained from tablets, pure metronidazole, and its silver(I) complexes was tested. The research was carried out in various environments, at different temperatures, in H2O2 solution, and during exposure to radiation (UV, sunlight). The greatest degradation was found in the alkaline environment and at higher temperatures. The silver(I) complexes exhibited relatively high stability under analyzed conditions that are higher than standard metronidazole solutions and tablets. The observations were confirmed by the kinetic and thermodynamic analysis. The described studies of new metronidazole silver(I) complexes increase the potential for their application in infections both in humans and animals.


Assuntos
Antibacterianos/química , Complexos de Coordenação/química , Peróxido de Hidrogênio/química , Metronidazol/química , Compostos de Prata/química , Animais , Cromatografia em Camada Delgada/métodos , Densitometria/métodos , Estabilidade de Medicamentos , Humanos , Cinética , Comprimidos
6.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298939

RESUMO

The present study deals with the mathematical modeling of crosslinking kinetics of polymer-phenol conjugates mediated by the Horseradish Peroxidase (HRP)-hydrogen peroxide (H2O2) initiation system. More specifically, a dynamic Monte Carlo (MC) kinetic model is developed to quantify the effects of crosslinking conditions (i.e., polymer concentration, degree of phenol substitution and HRP and H2O2 concentrations) on the gelation onset time; evolution of molecular weight distribution and number and weight average molecular weights of the crosslinkable polymer chains and gel fraction. It is shown that the MC kinetic model can faithfully describe the crosslinking kinetics of a finite sample of crosslinkable polymer chains with time, providing detailed molecular information for the crosslinkable system before and after the gelation point. The MC model is validated using experimental measurements on the crosslinking of a tyramine modified Hyaluronic Acid (HA-Tyr) polymer solution reported in the literature. Based on the rubber elasticity theory and the MC results, the dynamic evolution of hydrogel viscoelastic and molecular properties (i.e., number average molecular weight between crosslinks, Mc, and hydrogel mesh size, ξ) are calculated.


Assuntos
Ácido Hialurônico/química , Tiramina/química , Elasticidade , Peroxidase do Rábano Silvestre/química , Hidrogéis/química , Peróxido de Hidrogênio/química , Cinética , Modelos Teóricos , Método de Monte Carlo , Polímeros/química , Reologia
7.
Molecules ; 26(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207072

RESUMO

The aim of the research was to prepare low-cost adsorbents, including raw date pits and chemically treated date pits, and to apply these materials to investigate the adsorption behavior of Cr(III) and Cd(II) ions from wastewater. The prepared materials were characterized using SEM, FT-IR and BET surface analysis techniques for investigating the surface morphology, particle size, pore size and surface functionalities of the materials. A series of adsorption processes was conducted in a batch system and optimized by investigating various parameters such as solution pH, contact time, initial metal concentrations and adsorbent dosage. The optimum pH for achieving maximum adsorption capacity was found to be approximately 7.8. The determination of metal ions was conducted using atomic adsorption spectrometry. The experimental results were fitted using isotherm Langmuir and Freundlich equations, and maximum monolayer adsorption capacities for Cr(III) and Cd(II) at 323 K were 1428.5 and 1302.0 mg/g (treated majdool date pits adsorbent) and 1228.5 and 1182.0 mg/g (treated sagai date pits adsorbent), respectively. It was found that the adsorption capacity of H2O2-treated date pits was higher than that of untreated DP. Recovery studies showed maximal metal elution with 0.1 M HCl for all the adsorbents. An 83.3-88.2% and 81.8-86.8% drop in Cr(III) and Cd(II) adsorption, respectively, were found after the five regeneration cycles. The results showed that the Langmuir model gave slightly better results than the Freundlich model for the untreated and treated date pits. Hence, the results demonstrated that the prepared materials could be a low-cost and eco-friendly choice for the remediation of Cr(III) and Cd(II) contaminants from an aqueous solution.


Assuntos
Cádmio/química , Cromo/química , Metais Pesados/química , Phoeniceae/química , Sementes/química , Água/química , Adsorção , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
8.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281160

RESUMO

Silk fibroin (SF) has attracted much attention due to its high, tunable mechanical strength and excellent biocompatibility. Imparting the ability to respond to external stimuli can further enhance its scope of application. In order to imbue stimuli-responsive behavior in silk fibroin, we propose a new conjugated material, namely cationic SF (CSF) obtained by chemical modification of silk fibroin with ε-Poly-(L-lysine) (ε-PLL). This pH-responsive CSF hydrogel was prepared by enzymatic crosslinking using horseradish peroxidase and H2O2. Zeta potential measurements and SDS-PAGE gel electrophoresis show successful synthesis, with an increase in isoelectric point from 4.1 to 8.6. Fourier transform infrared (FTIR) and X-ray diffraction (XRD) results show that the modification does not affect the crystalline structure of SF. Most importantly, the synthesized CSF hydrogel has an excellent pH response. At 10 wt.% ε-PLL, a significant change in swelling with pH is observed. We further demonstrate that the hydrogel can be glucose-responsive by the addition of glucose oxidase (GOx). At high glucose concentration (400 mg/dL), the swelling of CSF/GOx hydrogel is as high as 345 ± 16%, while swelling in 200 mg/dL, 100 mg/dL and 0 mg/dL glucose solutions is 237 ± 12%, 163 ± 12% and 98 ± 15%, respectively. This shows the responsive swelling of CSF/GOx hydrogels to glucose, thus providing sufficient conditions for rapid drug release. Together with the versatility and biological properties of fibroin, such stimuli-responsive silk hydrogels have great potential in intelligent drug delivery, as soft matter substrates for enzymatic reactions and in other biomedical applications.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Fibroínas/química , Glucose/metabolismo , Hidrogéis/síntese química , Materiais Biocompatíveis/química , Liberação Controlada de Fármacos , Fibroínas/metabolismo , Glucose/química , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Polilisina/química , Seda/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X
9.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200865

RESUMO

A novel cytoplasmic dye-decolorizing peroxidase from Dictyostelium discoideum was investigated that oxidizes anthraquinone dyes, lignin model compounds, and general peroxidase substrates such as ABTS efficiently. Unlike related enzymes, an aspartate residue replaces the first glycine of the conserved GXXDG motif in Dictyostelium DyPA. In solution, Dictyostelium DyPA exists as a stable dimer with the side chain of Asp146 contributing to the stabilization of the dimer interface by extending the hydrogen bond network connecting two monomers. To gain mechanistic insights, we solved the Dictyostelium DyPA structures in the absence of substrate as well as in the presence of potassium cyanide and veratryl alcohol to 1.7, 1.85, and 1.6 Å resolution, respectively. The active site of Dictyostelium DyPA has a hexa-coordinated heme iron with a histidine residue at the proximal axial position and either an activated oxygen or CN- molecule at the distal axial position. Asp149 is in an optimal conformation to accept a proton from H2O2 during the formation of compound I. Two potential distal solvent channels and a conserved shallow pocket leading to the heme molecule were found in Dictyostelium DyPA. Further, we identified two substrate-binding pockets per monomer in Dictyostelium DyPA at the dimer interface. Long-range electron transfer pathways associated with a hydrogen-bonding network that connects the substrate-binding sites with the heme moiety are described.


Assuntos
Corantes/química , Dictyostelium/enzimologia , Heme/química , Peróxido de Hidrogênio/química , Peroxidase/química , Peroxidase/metabolismo , Catálise , Domínio Catalítico , Cristalografia por Raios X , Heme/metabolismo , Ligação de Hidrogênio , Oxirredução
10.
Anal Bioanal Chem ; 413(17): 4407-4416, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34081166

RESUMO

A novel copper-based metal-organic framework (Cu-MOF) with a large specific surface area and high porosity was synthesized. The Cu-MOF was a good peroxidase-mimicking enzyme and showed a high affinity with hydrogen peroxide in a wide pH range. The catalytic mechanism of Cu-MOF has been studied further based on comparing the characteristic of the Cu-MOF with some isomorphic MOFs. The catalytic activity center of Cu-MOF was determined to be the cupric ion rather than the ligand, which effectively promoted the generation of free radicals and electron transfer in the reaction progress. The high affinity of Cu-MOF to hydrogen peroxide proved it as an ideal catalyst for the chemiluminescence (CL) reaction involving hydrogen peroxide. Therefore, the CL method with high sensitivity could be established for detecting various substrates. A double-enzyme CL glucose biosensing platform was constructed for the determination of serum glucose employing the peroxidase-mimicking properties of Cu-MOF as well as glucose oxidase (GOx).


Assuntos
Técnicas Biossensoriais/métodos , Glicemia/análise , Cobre/química , Estruturas Metalorgânicas/química , Aspergillus niger/enzimologia , Catálise , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Medições Luminescentes/métodos , Modelos Moleculares , Peroxidase/química
11.
ACS Appl Mater Interfaces ; 13(24): 28010-28016, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34101422

RESUMO

The broad applications of implantable glucose biofuel cells (GBFCs) have become very attractive in biomedical sciences. The key challenge of GBFCs is eliminating the inevitable product H2O2 generated from the oxidation of glucose when glucose oxidase (GOx) is used as a catalyst while improving the performance of GBFCs. In this work, the cascade electrocatalyst, RBCs@NPDA was obtained through the in situ polymerization of dopamine to form nanopolydopamine (NPDA) on the surface of red blood cells (RBCs). The RBCs@NPDA can catalyze both fuels of H2O2 and O2, so as to generate a high cathodic current (0.414 mA cm-2). Furthermore, when RBCs@NPDA was used as a cathodic catalyst in the membraneless GBFC, it exhibited the cascade catalytic activity in the reduction of O2-H2O2 and minimized the damage to RBCs caused by the high concentration of H2O2. The mechanism research indicates that RBCs@NPDA integrates the property of NPDA and RBCs. Specifically, NPDA plays a catalase-like role in catalyzing the decomposition of H2O2, while RBCs play a laccase-like role in electrocatalyzing the O2 reduction reaction. This work offers the cascade catalyst for improving the performance of implantable GBFC and presents a strategy for constructing catalysts using living cells and nanomaterials to replace deformable and unstable enzymes in other biofuel cells.


Assuntos
Fontes de Energia Bioelétrica , Eritrócitos/metabolismo , Glucose/metabolismo , Indóis/química , Polímeros/química , Animais , Catálise , Eletrodos , Eritrócitos/química , Glucose/química , Glucose Oxidase/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Nanotubos de Carbono/química , Oxirredução , Oxigênio/química , Oxigênio/metabolismo , Suínos
12.
ACS Appl Mater Interfaces ; 13(24): 28650-28661, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34124895

RESUMO

Novel and effective radiosensitizers that can enhance radiosensitivity of tumor tissues and increase the local radiation dose are highly desirable. In this work, templated by bovine serum albumin (BSA), Bi2Se3-MnO2 nanocomposites (Bi2Se3-MnO2@BSA) were fabricated via biomineralization, while Bi2Se3 nanodots act as radiosensitizers to increase the local radiation dosage because of their strong X-ray attenuation ability, and MnO2 with catalase-like activity can increase the oxygen concentration in tumors by triggering the decomposition of tumor endogenous H2O2 so as to improve the hypoxia-associated radioresistance of tumors. Owing to the interaction of the two components in the interface, Bi2Se3-MnO2@BSA showed promoted catalytic activity compared to MnO2@BSA, favoring tumor radiotherapy (RT) sensitization. BSA templating enabled the nanocomposites with high colloidal stability and biocompatibility as well as satisfactory tumor targeting both in vitro and in vivo; thus, an enhanced RT efficacy was obtained. Moreover, the proposed Bi2Se3-MnO2@BSA exhibited excellent performances in computerized tomography and magnetic resonance imaging. Thus, this work provides a tumor microenvironment-responsive multifunctional theranostic nanoagent with an improved performance for imaging-guided tumor RT sensitization.


Assuntos
Antineoplásicos/uso terapêutico , Bismuto/uso terapêutico , Compostos de Manganês/uso terapêutico , Nanocompostos/uso terapêutico , Neoplasias/tratamento farmacológico , Óxidos/uso terapêutico , Radiossensibilizantes/uso terapêutico , Compostos de Selênio/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Bismuto/química , Catálise/efeitos da radiação , Bovinos , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Meios de Contraste/efeitos da radiação , Meios de Contraste/uso terapêutico , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Compostos de Manganês/química , Compostos de Manganês/efeitos da radiação , Camundongos Endogâmicos BALB C , Nanocompostos/química , Nanocompostos/efeitos da radiação , Neoplasias/diagnóstico por imagem , Óxidos/química , Óxidos/efeitos da radiação , Oxigênio/metabolismo , Medicina de Precisão , Radiossensibilizantes/síntese química , Radiossensibilizantes/efeitos da radiação , Compostos de Selênio/química , Compostos de Selênio/efeitos da radiação
13.
Molecules ; 26(11)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067394

RESUMO

Pharmaceuticals are found in waterbodies worldwide. Conventional sewage treatment plants are often not able to eliminate these micropollutants. Hence, Advanced Oxidation Processes (AOPs) have been heavily investigated. Here, metoprolol is exposed to UV irradiation, hydrogen peroxide, and ozonation. Degradation was analyzed using chemical kinetics both for initial and secondary products. Photo-induced irradiation enhanced by hydrogen peroxide addition accelerated degradation more than ozonation, leading to complete elimination. Degradation and transformation products were identified by high-performance liquid-chromatography coupled to high-resolution higher-order mass spectrometry. The proposed structures allowed to apply Quantitative Structure-Activity Relationship (QSAR) analysis to predict ecotoxicity. Degradation products were generally associated with a lower ecotoxicological hazard to the aquatic environment according to OECD QSAR toolbox and VEGA. Comparison of potential structural isomers suggested forecasts may become more reliable with larger databases in the future.


Assuntos
Ecotoxicologia , Metoprolol/análise , Ozônio/química , Relação Quantitativa Estrutura-Atividade , Esgotos/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Algoritmos , Reatores Biológicos , Cromatografia Líquida de Alta Pressão , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Metoprolol/química , Oxigênio/química , Fotoquímica , Fotólise , Software , Raios Ultravioleta , Poluentes Químicos da Água/química
14.
Ecotoxicol Environ Saf ; 221: 112422, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34144252

RESUMO

Homogeneous Cu2+-mediated activation of H2O2 has been widely applied for the removal of organic contaminants, but fairly high dosage of Cu2+ is generally required and may cause secondary pollution. In the present study, minute Cu2+ (2.5 µM) catalyzed H2O2 exhibited excellent efficiency in degradation of organic pollutants with the assistant of naturally occurring level HCO3- (1 mM). In a typical case, acetaminophen (ACE) was completely eliminated within 10 min which followed the pseudo-first-order kinetics. Singlet oxygen and superoxide radical rather than traditionally identified hydroxyl radical were the predominant reactive oxygen species (ROS) responsible for ACE degradation. Meanwhile, Cu3+ was deduced through Cu+ and p-hydroxybenzoic acid formation analysis. CuCO3(aq) was the main complex with high reactivity for the activation of H2O2 to form ROS and Cu3+. The removal efficiency of ACE depended on the operating parameters, such as Cu2+, HCO3- and H2O2 dosage, solution initial pH. The presence of Cl-, HPO42-, humic acid were found to retard ACE removal while other anions such as SO42- and NO3- had no obvious effect. ACE exhibited lower degradation efficiency in real water matrices than that in ultra-pure water. Nevertheless, 58-100% of ACE was removed from domestic wastewater, lake water and tap water within 60 min. Moreover, eight intermediate products were identified and the possible degradation pathways of ACE were proposed. Additionally, other typical organic pollutants including bisphenol A, norfloxacin, lomefloxacin hydrochloride and sulfadiazine, exhibited great removal efficiency in the Cu2+/H2O2/HCO3- system.


Assuntos
Acetaminofen/química , Bicarbonatos/química , Cobre/química , Peróxido de Hidrogênio/química , Espécies Reativas de Oxigênio/química , Poluentes Químicos da Água/química , Catálise , Compostos Orgânicos/química , Purificação da Água/métodos
15.
ACS Appl Mater Interfaces ; 13(26): 30274-30283, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34170100

RESUMO

In this work, an iron self-boosting polymer nanoenzyme was prepared by using pyrrole-3-carboxylic acid as a monomer and iron as an oxidizing agent via a simple and one-step method [hereafter referred to as FePPy nanoparticles (NPs)]. In fact, researchers previously paid negligible attention on the iron element during the polymerization reaction of polypyrrole, thus the intrinsically catalytic functions and enzymatic activities of the high iron content (wt %: 21.11%) are ignored and not fully explored. As expected, results demonstrate that the as-synthesized FePPy NPs can decompose H2O2 to generate hydroxyl radicals (•OH) which exhibit enzyme characteristics, further inducing a nonapoptotic ferroptosis pathway. Moreover, the nanoenzyme shows impressive photothermal properties which can accelerate the Fenton reactions to enhance ferroptosis. The combined photothermal and ferroptosis therapy of FePPy NPs was found to have high efficacy. With the properties of easy synthesis, high efficacy, and good biocompatibility, the FePPy NPs are considered as potential agents for cancer treatments.


Assuntos
Antineoplásicos/uso terapêutico , Ferroptose/efeitos dos fármacos , Nanoestruturas/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/efeitos da radiação , Ácidos Carboxílicos/química , Ácidos Carboxílicos/efeitos da radiação , Ácidos Carboxílicos/uso terapêutico , Catálise , Feminino , Células HeLa , Humanos , Peróxido de Hidrogênio/química , Radical Hidroxila/metabolismo , Ferro/química , Ferro/efeitos da radiação , Luz , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Terapia Fototérmica , Polímeros/química , Polímeros/efeitos da radiação , Polímeros/uso terapêutico , Pirróis/química , Pirróis/efeitos da radiação , Pirróis/uso terapêutico , Temperatura
16.
Int J Mol Sci ; 22(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068601

RESUMO

Cold atmospheric plasma (CAP) and plasma-treated liquids (PTLs) have recently become a promising option for cancer treatment, but the underlying mechanisms of the anti-cancer effect are still to a large extent unknown. Although hydrogen peroxide (H2O2) has been recognized as the major anti-cancer agent of PTL and may enable selectivity in a certain concentration regime, the co-existence of nitrite can create a synergistic effect. We develop a mathematical model to describe the key species and features of the cellular response toward PTL. From the numerical solutions, we define a number of dependent variables, which represent feasible measures to quantify cell susceptibility in terms of the H2O2 membrane diffusion rate constant and the intracellular catalase concentration. For each of these dependent variables, we investigate the regimes of selective versus non-selective, and of synergistic versus non-synergistic effect to evaluate their potential role as a measure of cell susceptibility. Our results suggest that the maximal intracellular H2O2 concentration, which in the selective regime is almost four times greater for the most susceptible cells compared to the most resistant cells, could be used to quantify the cell susceptibility toward exogenous H2O2. We believe our theoretical approach brings novelty to the field of plasma oncology, and more broadly, to the field of redox biology, by proposing new ways to quantify the selective and synergistic anti-cancer effect of PTL in terms of inherent cell features.


Assuntos
Peróxido de Hidrogênio/uso terapêutico , Neoplasias/terapia , Gases em Plasma/uso terapêutico , Soluções/uso terapêutico , Sinergismo Farmacológico , Humanos , Peróxido de Hidrogênio/química , Modelos Teóricos , Neoplasias/patologia , Nitritos/química , Nitritos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Soluções/efeitos da radiação
17.
Nat Commun ; 12(1): 3393, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099712

RESUMO

The iron gall ink-triggered chemical corrosion of hand-written documents is a big threat to Western cultural heritages, which was demonstrated to result from the iron gall (GA-Fe) chelate-promoted reactive oxygen species generation. Such a phenomenon has inspired us to apply the pro-oxidative mechanism of GA-Fe to anticancer therapy. In this work, we construct a composite cancer nanomedicine by loading gallate into a Fe-engineered mesoporous silica nanocarrier, which can degrade in acidic tumor to release the doped Fe3+ and the loaded gallate, forming GA-Fe nanocomplex in situ. The nanocomplex with a highly reductive ligand field can promote oxygen reduction reactions generating hydrogen peroxide. Moreover, the resultant two-electron oxidation form of GA-Fe is an excellent Fenton-like agent that can catalyze hydrogen peroxide decomposition into hydroxyl radical, finally triggering severe oxidative damage to tumors. Such a therapeutic approach by intratumoral synthesis of GA-Fe nano-metalchelate may be instructive to future anticancer researches.


Assuntos
Antineoplásicos/administração & dosagem , Ácido Gálico/administração & dosagem , Ferro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Catálise , Complexos de Coordenação/administração & dosagem , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Portadores de Fármacos/química , Feminino , Ácido Gálico/química , Ácido Gálico/metabolismo , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Radical Hidroxila/química , Radical Hidroxila/metabolismo , Injeções Intravenosas , Ferro/química , Ferro/metabolismo , Ligantes , Nanopartículas Metálicas/química , Camundongos , Neoplasias/patologia , Oxirredução , Oxigênio/metabolismo , Dióxido de Silício/química , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Mater Chem B ; 9(18): 3925-3934, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33942817

RESUMO

Nanozymes, as a kind of artificial mimic enzymes, have superior catalytic capacity and stability. As lack of O2 in tumor cells can cause resistance to drugs, we designed drug delivery liposomes (MnO2-PTX/Ce6@lips) loaded with catalase-like nanozymes of manganese dioxide nanoparticles (MnO2 NPs), paclitaxel (PTX) and chlorin e6 (Ce6) to consume tumor's native H2O2 and produce O2. Based on the catalysis of MnO2 NPs, a large amount of oxygen was produced by MnO2-PTX/Ce6@lips to burst the liposomes and achieve a responsive release of the loaded drug (paclitaxel), and the released O2 relieved the chemoresistance of tumor cells and provided raw materials for photodynamic therapy. Subsequently, MnO2 NPs were decomposed into Mn2+ in an acidic tumor environment to be used as contrast agents for magnetic resonance imaging. The MnO2-PTX/Ce6@lips enhanced the efficacy of chemotherapy and photodynamic therapy (PDT) in bearing-tumor mice, even achieving complete cure. These results indicated the great potential of MnO2-PTX/Ce6@lips for the modulation of the TME and the enhancement of chemotherapy and PDT along with MRI tracing in the treatment of tumors.


Assuntos
Nanoestruturas/uso terapêutico , Neoplasias/tratamento farmacológico , Nanomedicina Teranóstica , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/química , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Luz , Lipossomos/química , Imageamento por Ressonância Magnética , Compostos de Manganês/química , Camundongos , Nanopartículas/química , Nanoestruturas/química , Nanoestruturas/toxicidade , Neoplasias/diagnóstico por imagem , Óxidos/química , Oxigênio/química , Oxigênio/metabolismo , Paclitaxel/química , Paclitaxel/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química
20.
J Mater Chem B ; 9(17): 3677-3688, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33949613

RESUMO

Silk fibroin (SF), derived from Bombyx mori, is a category of fibrous protein with outstanding potential for applications in the biomedical and biotechnological fields. In spite of its many advantageous properties, the exploration of SF as a versatile nanodrug precursor for tumor therapy has still been restricted in recent years. Herein, a multifunctional SF-derived nanoplatform was facilely developed via encapsulating the photosensitizer chlorin e6 (Ce6) into MnO2-capped SF nanoparticles (NPs). SF@MnO2 nanocarriers were synthesized through a surface crystallization technique, using SF as a reductant and sacrificial template. Afterwards, Ce6 was covalently incorporated into the loose structure of the SF@MnO2 nanocarrier on the basis of adsorption to abundant peptide-binding sites. To modulate the tumor microenvironment (TME), SF@MnO2/Ce6 (SMC) NPs were capable of catalyzing the decomposition of H2O2 into O2, which can be converted into cytotoxic reactive oxygen species (ROS) during photodynamic therapy (PDT). Moreover, the MnO2 component was able to oxidize intracellular glutathione (GSH) into non-reducing glutathione disulfide (GSSG), and the consumption of GSH could significantly protect the local ROS from being reduced, which further augmented the therapeutic outcome of PDT. Via another angle, SMC NPs can produce strong hyperthermia under near-infrared (NIR) light activation, which was highly desirable for efficient photothermal therapy (PTT). Both in vitro and in vivo studies demonstrated the intense tumor inhibitory effects as a result of augmented PTT/PDT mediated by SMC NPs. We believe that this study may provide useful insights for employing SF-based nanocomposites for more medical applications in the near future.


Assuntos
Antineoplásicos/química , Fibroínas/química , Compostos de Manganês/química , Nanopartículas/química , Óxidos/química , Fármacos Fotossensibilizantes/química , Porfirinas/química , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Cristalização , Feminino , Glutationa/química , Dissulfeto de Glutationa/química , Humanos , Peróxido de Hidrogênio/química , Raios Infravermelhos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais , Oxirredução , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/química , Propriedades de Superfície
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