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1.
ACS Appl Mater Interfaces ; 13(33): 39076-39087, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34378375

RESUMO

Fluorophores with multifunctional properties known as rare-earth-doped nanoparticles (RENPs) are promising candidates for bioimaging, therapy, and drug delivery. When applied in vivo, these nanoparticles (NPs) have to retain long blood-circulation time, bypass elimination by phagocytic cells, and successfully arrive at the target area. Usually, NPs in a biological medium are exposed to proteins, which form the so-called "protein corona" (PC) around the NPs and influence their targeted delivery and accumulation in cells and tissues. Different surface coatings change the PC size and composition, subsequently deciding the fate of the NPs. Thus, detailed studies on the PC are of utmost importance to determine the most suitable NP surface modification for biomedical use. When it comes to RENPs, these studies are particularly scarce. Here, we investigate the PC composition and its impact on the cellular uptake of citrate-, SiO2-, and phospholipid micelle-coated RENPs (LiYF4:Yb3+,Tm3+). We observed that the PC of citrate- and phospholipid-coated RENPs is relatively stable and similar in the adsorbed protein composition, while the PC of SiO2-coated RENPs is larger and highly dynamic. Moreover, biocompatibility, accumulation, and cytotoxicity of various RENPs in cancer cells have been evaluated. On the basis of the cellular imaging, supported by the inhibition studies, it was revealed that RENPs are internalized by endocytosis and that specific endocytic routes are PC composition dependent. Overall, these results are essential to fill the gaps in the fundamental understanding of the nano-biointeractions of RENPs, pertinent for their envisioned application in biomedicine.


Assuntos
Materiais Revestidos Biocompatíveis/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Metais Terras Raras/química , Coroa de Proteína/metabolismo , Dióxido de Silício/química , Adsorção , Neoplasias da Mama , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Ácido Cítrico/química , Materiais Revestidos Biocompatíveis/metabolismo , Endocitose , Corantes Fluorescentes/metabolismo , Humanos , Tamanho da Partícula , Fosfolipídeos/química , Propriedades de Superfície
2.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360861

RESUMO

In response to the demand for high-performance materials, epoxy thermosetting and its composites are widely used in various industries. However, their poor toughness, resulting from the high crosslinking density of the epoxy network, must be improved to expand their application to the manufacturing of flexible products. In this study, ductile epoxy thermosetting was produced using thiol compounds with functionalities of 2 and 3 as curing agents. The mechanical properties of the epoxy were further enhanced by incorporating fumed silica into it. To increase the filler dispersion, epoxide-terminated polydimethylsiloxane was synthesized and used as a composite component. Thanks to the polysiloxane-silica interaction, the nanosilica was uniformly dispersed in the epoxy composites, and their mechanical properties improved with increasing fumed silica content up to 5 phr (parts per hundred parts of epoxy resin). The toughness and impact strength of the composite containing 5 phr nanosilica were 517 (±13) MJ/m3 and 69.8 (±1.3) KJ/m2, respectively.


Assuntos
Resinas Compostas/síntese química , Resinas Epóxi/síntese química , Dimetilpolisiloxanos/química , Teste de Materiais , Dióxido de Silício/química , Propriedades de Superfície , Resistência à Tração
3.
Molecules ; 26(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34361575

RESUMO

Glass ionomer cements and resin-based composites are promising materials in restorative dentistry. However, their limited mechanical properties and the risk of bulk/marginal fracture compromise their lifespan. Intensive research has been conducted to understand and develop new materials that can mimic the functional behavior of the oral cavity. Nanotechnological approaches have emerged to treat oral infections and become a part of scaffolds for tissue regeneration. Carbon nanotubes are promising materials to create multifunctional platforms for dental applications. This review provides a comprehensive survey of and information on the status of this state-of-the-art technology and describes the development of glass ionomers reinforced with carbon nanotubes possessing improved mechanical properties. The applications of carbon nanotubes in drug delivery and tissue engineering for healing infections and lesions of the oral cavity are also described. The review concludes with a summary of the current status and presents a vision of future applications of carbon nanotubes in the practice of dentistry.


Assuntos
Portadores de Fármacos , Teste de Materiais , Nanotubos de Carbono/química , Cimentos de Resina , Resinas Acrílicas/química , Resinas Acrílicas/uso terapêutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Humanos , Cimentos de Resina/química , Cimentos de Resina/uso terapêutico , Dióxido de Silício/química , Dióxido de Silício/uso terapêutico , Propriedades de Superfície
4.
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
5.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361087

RESUMO

Silica/biopolymer hydrogel-based materials constitute very attractive platforms for various emerging biomedical applications, particularly for bone repair. The incorporation of calcium phosphates in the hybrid network allows for designing implants with interesting biological properties. Here, we introduce a synthesis procedure for obtaining silica-chitosan (CS)-tricalcium phosphate (TCP) xerogels, with CS nominal content varying from 4 to 40 wt.% and 10 to 20 wt.% TCP. Samples were obtained using the sol-gel process assisted with ultrasound probe, and the influence of ethanol or water as washing solvents on surface area, micro- and mesopore volume, and average pore size were examined in order to optimize their textural properties. Three washing solutions with different soaking conditions were tested: 1 or 7 days in absolute ethanol and 30 days in distilled water, resulting in E1, E7, and W30 washing series, respectively. Soaked samples were eventually dried by evaporative drying at air ambient pressure, and the formation of interpenetrated hybrid structures was suggested by Fourier transformed infrared (FTIR) spectroscopy. In addition the impact that both washing solvent and TCP content have on the biodegradation, in vitro bioactivity and osteoconduction of xerogels were explored. It was found that calcium and phosphate-containing ethanol-washed xerogels presented in vitro release of calcium (2-12 mg/L) and silicon ions (~60-75 mg/L) after one week of soaking in phosphate-buffered saline (PBS), as revealed by inductive coupled plasma (ICP) spectroscopy analysis. However, only the release of silicon was detected for water-washed samples. Besides, all the samples exhibited in vitro bioactivity in simulated body fluid (SBF), as well as enhanced in vitro cell growth and also significant focal adhesion development and maturation.


Assuntos
Regeneração Óssea , Fosfatos de Cálcio/química , Quitosana/química , Géis/química , Osteoblastos/citologia , Dióxido de Silício/química , Solventes/química , Materiais Biocompatíveis/química , Líquidos Corporais , Células Cultivadas , Humanos , Teste de Materiais
6.
Phys Chem Chem Phys ; 23(33): 18001-18011, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34382985

RESUMO

A hydrophobic heptapeptide, with sequence AFILPTG, as part of a phage capsid protein binds effectively to silica particles carrying negative charge. Here, we explore the silica binding activity of the sequence as a short polypeptide with polar N and C terminals. To describe the structural changes that occur on binding, we fit experimental infrared, Raman and circular dichroism data for a number of structures simulated in the full configuration space of the hepta-peptide using replica exchange molecular dynamics. Quantum chemistry was used to compute normal modes of infrared and Raman spectra and establish a relationship to structures from MD data. To interpret the circular dichroism data, instead of empirical factoring of optical activity into helical/sheet/random components, we exploit natural transition orbital theory and specify the contributions of backbone amide units, side chain functional groups, water, sodium ions and silica to the observed transitions. Computed optical responses suggest a less folded backbone and importance of the N-terminal when close to silica. We further discuss the thermodynamics of the interplay of charged and hydrophobic moieties of the polypeptide on association with the silica surface. The outcomes of this study may assist in the engineering of novel artificial bio-silica heterostructures.


Assuntos
Oligopeptídeos/química , Dióxido de Silício/química , Teoria da Densidade Funcional , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Desdobramento de Proteína , Dióxido de Silício/síntese química , Propriedades de Superfície
7.
Int J Nanomedicine ; 16: 4631-4642, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262273

RESUMO

Purpose: Antibiotic-resistant bacteria are pathogens that have emerged as a serious public health risk. Thus, there is an urgent need to develop a new generation of anti-bacterial materials to kill antibiotic-resistant bacteria. Methods: Nanosilver-decorated mesoporous organosilica nanoparticles (Ag-MONs) were fabricated for co-delivery of gentamicin (GEN) and nanosilver. After investigating the glutathione (GSH)-responsive matrix degradation and controlled release of both GEN and silver ions, the anti-bacterial activities of Ag-MONs@GEN were systematically determined against several antibiotic-susceptible and antibiotic-resistant bacteria including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis. Furthermore, the cytotoxic profiles of Ag-MONs@GEN were evaluated. Results: The GEN-loaded nanoplatform (Ag-MONs@GEN) showed glutathione-responsive matrix degradation, resulting in the simultaneous controlled release of GEN and silver ions. Ag-MONs@GEN exhibited excellent anti-bacterial activities than Ag-MONs and GEN alone via inducing ROS generation, especially enhancing synergetic effects against four antibiotic-resistant bacteria including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis. Moreover, the IC50 values of Ag-MONs@GEN in L929 and HUVECs cells were 313.6 ± 15.9 and 295.7 ± 12.3 µg/mL, respectively, which were much higher than their corresponding minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Conclusion: Our study advanced the development of Ag-MONs@GEN for the synergistic and safe treatment of antibiotic-resistant bacteria.


Assuntos
Resistência Microbiana a Medicamentos/efeitos dos fármacos , Gentamicinas/farmacologia , Glutationa/química , Nanopartículas/química , Dióxido de Silício/química , Prata/química , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura
8.
Molecules ; 26(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299461

RESUMO

Hierarchically porous materials, such as wrinkled mesoporous silica (WMS), have gained interest in the last couple of decades, because of their wide range of applications in fields such as nanomedicine, energy, and catalysis. The mechanism of formation of these nanostructures is not fully understood, despite various groups reporting very comprehensive studies. Furthermore, achieving particle diameters of 100 nm or less has proven difficult. In this study, the effects on particle size, pore size, and particle morphology of several co-solvents were evaluated. Additionally, varying concentrations of acid during synthesis affected the particle sizes, yielding particles smaller than 100 nm. The morphology and physical properties of the nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and dynamic light scattering (DLS). Homogeneous and spherical WMS, with the desired radial wrinkle morphology and particle sizes smaller than 100 nm, were obtained. The effect of the nature of the co-solvents and the concentration of acid are explained within the frame of previously reported mechanisms of formation, to further elucidate this intricate process.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas Metálicas/química , Dióxido de Silício/química , Adsorção , Portadores de Fármacos/química , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Nanopartículas/química , Nanoestruturas/química , Tamanho da Partícula , Porosidade , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
9.
Ultrason Sonochem ; 76: 105667, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34265634

RESUMO

Use of nanomaterials to remove uranium by adsorption from nuclear wastewater is widely applied, though not much work is focused on the recovery of uranium from the sorbents. The present work reports the recovery of adsorbed uranium from the microstructures of silica nanoparticles (SiO2M) and its functionalized biohybrid (fBHM), synthesized with Streptococcus lactis cells and SiO2M, intensified using ultrasound. Effects of temperature, concentration of leachant (nitric acid), sonic intensity, and operating frequency on the recovery as well as kinetics of recovery were thoroughly studied. A comparison with the silent operation demonstrated five and two fold increase due to the use of ultrasound under optimum conditions in the dissolution from SiO2M and fBHM respectively. Results of the subsequent adsorption studies using both the sorbents after sonochemical desorption have also been presented with an aim of checking the efficacy of reusing the adsorbent back in wastewater treatment. The SiO2M and fBHM adsorbed 69% and 67% of uranium respectively in the second cycle. The adsorption capacity of fBHM was found to reduce from 92% in the first cycle to 67% due to loss of adsorption sites in the acid treatment. Recovery and reuse of both the nuclear material and the sorbent (with some make up or activation) would ensure an effective nuclear remediation technique, catering to UN's Sustainable Development Goals.


Assuntos
Nanopartículas/química , Dióxido de Silício/química , Sonicação , Urânio/química , Urânio/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Temperatura
10.
Chem Pharm Bull (Tokyo) ; 69(7): 698-701, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34193718

RESUMO

By employing a silica-coated magnetite as a catalyst, a silica-catalyzed carboxylative cyclization of propargylic amines with carbon dioxide (CO2) proceeded to afford the corresponding 2-oxazolidinones. Moreover, after the reaction, the silica-coated magnetic catalyst was readily recovered by use of an external magnet and could be reused up to six times without deactivation.


Assuntos
Aminas/química , Dióxido de Carbono/química , Magnetismo , Dióxido de Silício/química , Catálise , Ciclização , Oxazolidinonas/química
11.
Molecules ; 26(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209621

RESUMO

Silica nanoparticles (SiO2 NPs) synthesized by the Stober method were used as drug delivery vehicles. Doxorubicin hydrochloride (DOX·HCl) is a chemo-drug absorbed onto the SiO2 NPs surfaces. The DOX·HCl loading onto and release from the SiO2 NPs was monitored via UV-VIS and fluorescence spectra. Alternatively, the zeta potential was also used to monitor and evaluate the DOX·HCl loading process. The results showed that nearly 98% of DOX·HCl was effectively loaded onto the SiO2 NPs' surfaces by electrostatic interaction. The pH-dependence of the process wherein DOX·HCl release out of DOX·HCl-SiO2 NPs was investigated as well. For comparison, both the free DOX·HCl molecules and DOX·HCl-SiO2 NPs were used as the labels for cultured cancer cells. Confocal laser scanning microscopy images showed that the DOX·HCl-SiO2 NPs were better delivered to cancer cells which are more acidic than healthy cells. We propose that engineered DOX·HCl-SiO2 systems are good candidates for drug delivery and clinical applications.


Assuntos
Antineoplásicos , Doxorrubicina , Portadores de Fármacos , Nanopartículas , Neoplasias , Dióxido de Silício , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Humanos , Células MCF-7 , Microscopia Confocal , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Dióxido de Silício/farmacologia
12.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207149

RESUMO

In this study, four different coal fly ashes (CFAs) were used as raw materials of silica and alumina for the preparation of the alumina-containing Mobil Composition of Matter No. 41 (Al-MCM-41) and the exploration of an activation strategy that is efficient and universal for various CFAs. Alkaline hydrothermal and alkaline fusion activations proceeded at different temperatures to determine the best treatment parameters. We controlled the pore structure and surface hydroxyl density of the CFA-derived Al-MCM-41 by changing the crystallization temperature and aging time. The products were characterized by small-angle X-ray diffraction, nitrogen isotherms, Fourier-transform infrared spectroscopy, 29Si silica magic-angle spinning nuclear magnetic resonance, and transmission electron microscopy, and they were then grafted with thiol groups to remove Pb(II) from aqueous solutions. This paper innovatively evaluates the CFA activation strategies using energy consumption analysis and determines the optimal activation methodology and parameters. This paper also unveils the effect of the crystallization condition of Al-MCM-41 on its subsequent Pb(II) removal capacity. The results show that the appropriate selection of crystallization parameters can considerably increase the removal capacity over Pb(II), providing a new path to tackle the ever-increasing concern of aquic heavy-metal pollution.


Assuntos
Óxido de Alumínio/química , Cinza de Carvão/química , Carvão Mineral/análise , Chumbo/química , Dióxido de Silício/química , Algoritmos , Cristalização , Modelos Teóricos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
Nat Commun ; 12(1): 4556, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315880

RESUMO

The potential applications of covalent organic frameworks (COFs) can be further developed by encapsulating functional nanoparticles within the frameworks. However, the synthesis of monodispersed core@shell structured COF nanocomposites without agglomeration remains a significant challenge. Herein, we present a versatile dual-ligand assistant strategy for interfacial growth of COFs on the functional nanoparticles with abundant physicochemical properties. Regardless of the composition, geometry or surface properties of the core, the obtained core@shell structured nanocomposites with controllable shell-thickness are very uniform without agglomeration. The derived bowl-shape, yolk@shell, core@satellites@shell nanostructures can also be fabricated delicately. As a promising type of photosensitizer for photodynamic therapy (PDT), the porphyrin-based COFs were grown onto upconversion nanoparticles (UCNPs). With the assistance of the near-infrared (NIR) to visible optical property of UCNPs core and the intrinsic porosity of COF shell, the core@shell nanocomposites can be applied as a nanoplatform for NIR-activated PDT with deep tissue penetration and chemotherapeutic drug delivery.


Assuntos
Estruturas Metalorgânicas/química , Nanopartículas/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Ligantes , Camundongos Endogâmicos BALB C , Nanocompostos/química , Nanopartículas/ultraestrutura , Fotoquimioterapia , Porfirinas/química , Dióxido de Silício/química , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/patologia
14.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298923

RESUMO

In the following study, polyurethane (PUR) composites were modified with 2 wt.% of walnut shell filler modified with selected mineral compounds-perlite, montmorillonite, and halloysite. The impact of modified walnut shell fillers on selected properties of PUR composites, such as rheological properties (dynamic viscosity, foaming behavior), mechanical properties (compressive strength, flexural strength, impact strength), dynamic-mechanical behavior (glass transition temperature, storage modulus), insulation properties (thermal conductivity), thermal characteristic (temperature of thermal decomposition stages), and flame retardant properties (e.g., ignition time, limiting oxygen index, heat peak release) was investigated. Among all modified types of PUR composites, the greatest improvement was observed for PUR composites filled with walnut shell filler functionalized with halloysite. For example, on the addition of such modified walnut shell filler, the compressive strength was enhanced by ~13%, flexural strength by ~12%, and impact strength by ~14%. Due to the functionalization of walnut shell filler with thermally stable flame retardant compounds, such modified PUR composites were characterized by higher temperatures of thermal decomposition. Most importantly, PUR composites filled with flame retardant compounds exhibited improved flame resistance characteristics-in all cases, the value of peak heat release was reduced by ~12%, while the value of total smoke release was reduced by ~23%.


Assuntos
Óxido de Alumínio/química , Bentonita/química , Argila/química , Resinas Compostas/química , Juglans/química , Poliuretanos/química , Dióxido de Silício/química , Força Compressiva , Vidro/química , Teste de Materiais/métodos , Temperatura , Viscosidade
15.
ACS Appl Mater Interfaces ; 13(27): 32295-32306, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34196538

RESUMO

Synthetic fungicides have been widely used to protect crops from fungal diseases. However, excessive use of synthetic fungicides leads to the generation of fungicide resistance in fungal pathogens. Recently, smart cargo delivery systems have been introduced for the construction of a pesticide delivery nanoplatform, benefiting from their controlled release performance. Herein, a fungal pathogen microenvironment-responsive supramolecular fungicide nanoplatform has been designed and constructed, using quaternary ammonium salt (Q)-modified mesoporous silica nanoparticles (MSN-Q NPs) as nanocarriers loaded with berberine hydrochloride (BH) and carboxylatopillar[5]arene (CP[5]A) as nanogates to form BH-loaded CP[5]A@MSN-Q NPs for effective inhibition of Botrytis cinerea. CP[5]A as nanogates can endow the fungicide nanoplatform with pH stimuli-responsive release features for the control of fungicide release. The loaded BH, as a natural plant fungicide, provides an ecofriendly alternative to synthetic fungicides for controlling B. cinerea. Interestingly, we use oxalic acid (OA) secreted by B. cinerea as a trigger so that BH can be released from the fungicide nanoplatform on demand under pathogen microenvironments for controlling B. cinerea. The experimental results indicate that the fabricated fungicide nanoplatform could effectively inhibit the mycelial growth and spore germination, providing a new way for the management of B. cinerea in actual application.


Assuntos
Portadores de Fármacos/química , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Nanopartículas/química , Dióxido de Silício/química , Berberina/química , Berberina/farmacologia , Botrytis/efeitos dos fármacos , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Porosidade , Compostos de Amônio Quaternário/química
16.
ACS Appl Mater Interfaces ; 13(27): 31495-31513, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34219455

RESUMO

Owing to their fast but tunable degradation kinetics (in comparison to silicates) and excellent bioactivity, the past decade has witnessed an upsurge in the research interest of borate/borosilicate-based bioactive glasses for their potential use in a wide range of soft tissue regeneration applications. Nevertheless, most of these glasses have been developed using trial-and-error approaches wherein SiO2 has been gradually replaced by B2O3. One major reason for using this empirical approach is the complexity of short-to-intermediate range structures of these glasses which greatly complicate the development of a thorough understanding of composition-structure-solubility relationships in these systems. Transitioning beyond the current style of composition design to a style that facilitates the development of bioactive glasses with controlled ion release tailored for specific patients/diseases requires a deeper understanding of the compositional/structural dependence of glass degradation behavior in vitro and in vivo. Accordingly, the present study aims to decipher the structural drivers controlling the dissolution kinetics and ion-release behavior of potentially bioactive glasses designed in the Na2O-B2O3-P2O5-SiO2 system across a broad compositional space in simulated body environments (pH = 7.4). By employing state-of-the-art spectroscopy-based characterization techniques, it has been shown that the degradation kinetics of borosilicate glasses depend on their R (Na2O/B2O3) and K (SiO2/B2O3) ratios, while the release of particular network-forming moieties from the glass into solution is strongly influenced by their role in-and effect on-the short-to-intermediate-range molecular structure. The current study aims to promote a rational design of borosilicate-based bioactive glasses, where a delicate balance between maximizing soft tissue regeneration and minimizing calcification and cytotoxicity can be achieved by tuning the release of ionic dissolution products (of controlled identity and abundance) from bioactive glasses into physiological media.


Assuntos
Boro/química , Portadores de Fármacos/química , Vidro/química , Silicatos/química , Desenho de Fármacos , Fenômenos Mecânicos , Dióxido de Silício/química , Solubilidade
17.
Int J Nanomedicine ; 16: 4409-4430, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234434

RESUMO

It is a fact that the use of antibiotics is inducing a growing resistance on bacteria. This situation is not only the consequence of a drugs' misuse, but a direct consequence of a widespread and continuous use. Current studies suggest that this effect could be reversed by using abandoned antibiotics to which bacteria have lost their resistance, but this is only a temporary solution that in near future would lead to new resistance problems. Fortunately, current nanotechnology offers a new life for old and new antibiotics, which could have significantly different pharmacokinetics when properly delivered; enabling new routes able to bypass acquired resistances. In this contribution, we will focus on the use of porous silica nanoparticles as functional carriers for the delivery of antibiotics and biocides in combination with additional features like membrane sensitizing and heavy metal-driven metabolic-disrupting therapies as two of the most interesting combination therapies.


Assuntos
Antibacterianos/química , Infecções Bacterianas/tratamento farmacológico , Portadores de Fármacos/química , Nanopartículas/química , Dióxido de Silício/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Porosidade
18.
Int J Mol Sci ; 22(14)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34299286

RESUMO

Mesoporous silica nanoparticles (MSN) were synthesised and functionalised with triethylenetetramine (MSN-TETA). The samples were fully characterised (transmission electron microscopy, small angle X-ray scattering, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential and nitrogen adsorption/desorption isotherms) and used as carriers for the adsorption of the antimicrobial drug sulphamethizole (SMZ). SMZ loading, quantified by UV-Vis spectroscopy, was higher on MSN-TETA (345.8 mg g-1) compared with bare MSN (215.4 mg g-1) even in the presence of a lower surface area (671 vs. 942 m2 g-1). The kinetics of SMZ adsorption on MSN and MSN-TETA followed a pseudo-second-order model. The adsorption isotherm is described better by a Langmuir model rather than a Temkin or Freundlich model. Release kinetics showed a burst release of SMZ from bare MSN samples (k1 = 136 h-1) in contrast to a slower release found with MSN-TETA (k1 = 3.04 h-1), suggesting attractive intermolecular interactions slow down SMZ release from MSN-TETA. In summary, the MSN surface area did not influence SMZ adsorption and release. On the contrary, the design of an effective drug delivery system must consider the intermolecular interactions between the adsorbent and the adsorbate.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Dióxido de Silício/química , Sulfametizol/metabolismo , Trientina/química , Adsorção , Liberação Controlada de Fármacos , Cinética , Microscopia Eletrônica de Transmissão/métodos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Sulfametizol/química , Difração de Raios X/métodos
19.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34210022

RESUMO

Food additive amorphous silicon dioxide (SiO2) particles are manufactured by two different methods-precipitated and fumed procedures-which can induce different physicochemical properties and biological fates. In this study, precipitated and fumed SiO2 particles were characterized in terms of constituent particle size, hydrodynamic diameter, zeta potential, surface area, and solubility. Their fates in intestinal cells, intestinal barriers, and tissues after oral administration in rats were determined by optimizing Triton X-114-based cloud point extraction (CPE). The results demonstrate that the constituent particle sizes of precipitated and fumed SiO2 particles were similar, but their aggregate states differed from biofluid types, which also affect dissolution properties. Significantly higher cellular uptake, intestinal transport amount, and tissue accumulation of precipitated SiO2 than of fumed SiO2 was found. The intracellular fates of both types of particles in intestinal cells were primarily particle forms, but slowly decomposed into ions during intestinal transport and after distribution in the liver, and completely dissolved in the bloodstream and kidneys. These findings will provide crucial information for understanding and predicting the potential toxicity of food additive SiO2 after oral intake.


Assuntos
Intestinos/química , Dióxido de Silício/administração & dosagem , Dióxido de Silício/síntese química , Administração Oral , Animais , Análise Química do Sangue , Células CACO-2 , Linhagem Celular Tumoral , Precipitação Química , Feminino , Humanos , Intestinos/citologia , Rim/química , Fígado/química , Nanopartículas , Octoxinol/química , Tamanho da Partícula , Ratos , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Solubilidade
20.
Theranostics ; 11(14): 6735-6745, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093850

RESUMO

Background: Nucleic acid (NA)-based diagnostics enable a rapid response to various diseases, but current techniques often require multiple labor-intensive steps, which is a major obstacle to successful translation to a clinical setting. Methods: We report on a surface-engineered single-chamber device for NA extraction and in situ amplification without sample transfer. Our system has two reaction sites: a NA extraction chamber whose surface is patterned with micropillars and a reaction chamber filled with reagents for in situ polymerase-based NA amplification. These two sites are integrated in a single microfluidic device; we applied plastic injection molding for cost-effective, mass-production of the designed device. The micropillars were chemically activated via a nature-inspired silica coating to possess a specific affinity to NA. Results: As a proof-of-concept, a colorimetric pH indicator was coupled to the on-chip analysis of NA for the rapid and convenient detection of pathogens. The NA enrichment efficiency was dependent on the lysate incubation time, as diffusion controls the NA contact with the engineered surface. We could detect down to 1×103 CFU by the naked eye within one hour of the total assay time. Conclusion: We anticipate that the surface engineering technique for NA enrichment could be easily integrated as a part of various types of microfluidic chips for rapid and convenient nucleic acid-based diagnostics.


Assuntos
DNA Bacteriano/análise , Dispositivos Lab-On-A-Chip , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Ácidos Nucleicos/isolamento & purificação , Colorimetria/métodos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Microfluídica/métodos , Microscopia Eletrônica de Varredura , Cimento de Policarboxilato/química , Reação em Cadeia da Polimerase em Tempo Real , Dióxido de Silício/química , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Propriedades de Superfície
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