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1.
Int J Nanomedicine ; 16: 2501-2513, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33824588

RESUMEN

Introduction: Aim to obtain a NO donor that can control released NO in vivo with the high efficacy of tumor suppression and targeting, a nanoplatform consisting of FA-Fe3O4@mSiO2-Au/DOX was constructed. Methods: In vitro, the nanoplatform catalyzed NO's release with the maximum value of 4.91 µM within 60 min at 43°C pH=5.0, which was increased by 1.14 times when the temperature was 37°C. In vivo, 11.7 µg Au in the tumor tissue was found to catalyze S-nitrosoglutathione continuously, and 54 µM NO was checked out in the urine. Results and Discussion: The high concentration of NO was found to increase the apoptotic rate and to reduce tumor proliferation. In the chemo-photothermal combination therapy, the tumor inhibition rate was increased up to 94.3%, and Au's contribution from catalyzing NO release NO was 8.17%.


Asunto(s)
Oro/química , Neoplasias/patología , Neoplasias/terapia , Óxido Nítrico/metabolismo , Catálisis , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Liberación de Fármacos , Endocitosis/efectos de los fármacos , Ácido Fólico/química , Humanos , Células MCF-7 , Fenómenos Magnéticos , Nanopartículas/química , Nanopartículas/ultraestructura , Tamaño de la Partícula , Porosidad , Silicio/química , Difracción de Rayos X
2.
Sensors (Basel) ; 21(4)2021 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-33668616

RESUMEN

This review summarizes the leading advancements in porous silicon (PSi) optical-biosensors, achieved over the past five years. The cost-effective fabrication process, the high internal surface area, the tunable pore size, and the photonic properties made the PSi an appealing transducing substrate for biosensing purposes, with applications in different research fields. Different optical PSi biosensors are reviewed and classified into four classes, based on the different biorecognition elements immobilized on the surface of the transducing material. The PL signal modulation and the effective refractive index changes of the porous matrix are the main optical transduction mechanisms discussed herein. The approaches that are commonly employed to chemically stabilize and functionalize the PSi surface are described.


Asunto(s)
Técnicas Biosensibles , Silicio , Fotones , Porosidad
3.
Int J Nanomedicine ; 16: 1929-1942, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727807

RESUMEN

Background: Staphylococcus aureus biofilms pose a unique challenge in healthcare due to their tolerance to a wide range of antimicrobial agents. The high cost and lengthy timeline to develop novel therapeutic agents have pushed researchers to investigate the use of nanomaterials to deliver antibiofilm agents and target biofilm infections more efficiently. Previous studies have concentrated on improving the efficacy of antibiotics by deploying nanoparticles as nanocarriers. However, the dispersal of the extracellular polymeric substance (EPS) matrix in biofilm-associated infections is also critical to the development of novel nanoparticle-based therapies. Methods: This study evaluated the efficacy of enzyme-functionalized mesoporous silica nanoparticles (MSNs) against methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) biofilms. MSNs were functionalized with the enzyme lysostaphin, which causes cell lysis of S. aureus bacteria. This was combined with two other enzyme functionalized MSNs, serrapeptase and DNase I which will degrade protein and eDNA in the EPS matrix, to enhance eradication of the biofilm. Cell viability after treatment with enzyme-functionalized MSNs was assessed using a MTT assay and CLSM, while crystal violet staining was used to assess EPS removal. Results: The efficacy of all three enzymes against S. aureus cells and biofilms was significantly improved when they were immobilized onto MSNs. Treatment efficacy was further enhanced when the three enzymes were used in combination against both MRSA and MSSA. Regardless of biofilm maturity (24 or 48 h), near-complete dispersal and killing of MRSA biofilms were observed after treatment with the enzyme-functionalized MSNs. Disruption of mature MSSA biofilms with a polysaccharide EPS was less efficient, but cell viability was significantly reduced. Conclusion: The combination of these three enzymes and their functionalization onto nanoparticles might extend the therapeutic options for the treatment of S. aureus infections, particularly those with a biofilm component.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Enzimas/metabolismo , Nanopartículas/química , Dióxido de Silicio/química , Staphylococcus aureus/fisiología , Biomasa , Supervivencia Celular , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Humanos , Staphylococcus aureus Resistente a Meticilina/fisiología , Pruebas de Sensibilidad Microbiana , Nanopartículas/ultraestructura , Porosidad
4.
Int J Nanomedicine ; 16: 1961-1976, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727809

RESUMEN

Introduction: Metastatic breast cancer seriously harms women's health and is currently the tumour type with the highest mortality rate in women. Recently, the combinatorial therapeutic approaches that integrate anti-cancer drugs and genetic agents is an attractive and promising strategy for the treatment of metastatic breast cancer. Moreover, such a combination strategy requires better drug carriers that can effectively deliver the cargo to the breast cancer cells and achieve controlled release in the cells to achieve better therapeutic effects. Methods: The tumour-targeted and redox-responsive mesoporous silica nanoparticles (MSNs) functionalised with DNA aptamers (AS1411) as a co-delivery system was developed and investigated for the potential against metastatic breast cancer. Doxorubicin (Dox) was loaded onto the MSNs, while AS1411 and a small interfering RNA (siTIE2) were employed as gatekeepers via attachment to the MSNs with redox-sensitive disulfide bonds. Results: The controlled release of Dox and siTIE2 was associated with intracellular glutathione. AS1411 mediated the targeted delivery of Dox by increasing its cellular uptake in metastatic breast cancer, ultimately resulting in a lower IC50 in MDA-MB-231 cells (human breast cancer cell line with high metastatic potency), improved biodistribution in tumour-bearing mice, and enhanced in vivo anti-tumour effects. The in vitro cell migration/invasion assay and in vivo anti-metastatic study revealed synergism in the co-delivery system that suppresses cancer cell metastasis. Conclusion: The tumour-targeted and redox-responsive MSN prepared in this study are promising for the effective delivery and controlled release of Dox and siTIE2 for improved treatment of metastatic breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/uso terapéutico , Nanopartículas/química , ARN Interferente Pequeño/administración & dosificación , Dióxido de Silicio/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/patología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/farmacología , Preparaciones de Acción Retardada/uso terapéutico , Doxorrubicina/farmacología , Portadores de Fármacos/química , Endocitosis/efectos de los fármacos , Femenino , Células HEK293 , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/ultraestructura , Invasividad Neoplásica , Metástasis de la Neoplasia , Oxidación-Reducción , Porosidad , ARN Interferente Pequeño/farmacología , Distribución Tisular/efectos de los fármacos
5.
Molecules ; 26(4)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673084

RESUMEN

The controlled design of robust, well reproducible, and functional nanomaterials made according to simple processes is of key importance to envision future applications. In the field of porous materials, tuning nanoparticle features such as specific area, pore size and morphology by adjusting simple parameters such as pH, temperature or solvent is highly needed. In this work, we address the tunable control of the pore morphology of mesoporous silica (MS) nanoparticles (NPs) with the sol-gel reaction temperature (Tsg). We show that the pore morphology of MS NPs alone or of MS shell covering iron oxide nanoparticles (IO NPs) can be easily tailored with Tsg orienting either towards stellar (ST) morphology (large radial pore of around 10 nm) below 80 °C or towards a worm-like (WL) morphology (small randomly oriented pores channel network, of 3-4 nm pore size) above 80 °C. The relaxometric and magnetothermal features of IO@STMS or IO@WLMS core shell NPs having respectively stellar or worm-like morphologies are compared and discussed to understand the role of the pore structure for MRI and magnetic hyperthermia applications.


Asunto(s)
Portadores de Fármacos/química , Nanopartículas/química , Dióxido de Silicio/química , Concentración de Iones de Hidrógeno , Imagen por Resonancia Magnética , Nanopartículas/ultraestructura , Tamaño de la Partícula , Porosidad , Temperatura
6.
Carbohydr Polym ; 260: 117765, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712123

RESUMEN

Chitosan (CS) combined with hydroxyapatite (HA) was injected into a composite braid, and a hierarchical pore structure scaffold was obtained by freeze drying and cold atmospheric plasma (CAP) technology. The CS/HA/braid scaffold with hierarchical pore structure was analyzed and characterized by scanning electronic microscopy, Fourier transform infrared spectroscopy, true color confocal microscopy, improved liquid replacement method, and phosphate buffer solution immersion. The mechanical properties and degradation ability of the scaffold were evaluated through compression test and degradation test. Results showed that HA addition endowed the core of the scaffold with macroscopic pore sizes of 80-180 µm, and CAP treatment endowed the shell of the scaffold with microscopic pore sizes ≤10 µm. All scaffolds exhibited high porosity and swelling rates of ≥80 % and ≥300 %, respectively. The scaffold with a hierarchical pore structure had good mechanical properties and twice the degradation rate. In addition, the treated scaffold precipitated intact spherical HA crystals. Under the synergistic effect of HA and CAP treatment, scaffolds achieved 277.6 % cell viability compared with pure CS scaffold. Overall, this method was feasible for preparing bone scaffolds with hierarchical pore structure for potential bone tissue engineering.


Asunto(s)
Quitosano/química , Durapatita/química , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Fuerza Compresiva , Liofilización , Ratones , Porosidad
7.
Carbohydr Polym ; 260: 117767, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712125

RESUMEN

Wound healing is a dynamic and intricate process, and newly dressings are urgently needed to promote wound healing over the multiple stages. Herein, two water-soluble adenine-modified chitosan (CS-A) derivatives were synthesized in aqueous solutions and freeze-dried to obtain porous sponge-like dressings. The novel derivatives displayed antibacterial activities against S. aureus and E. coli. Moreover, CS-A derivatives demonstrated excellent hemocompatibility and cytocompatibility, as well as promoted the proliferation of the wound cells by shortening the G1 phase and improving DNA duplication efficiency. The ability of CS-A sponges to promote wound healing was studied in a full-thickness skin defect model. The histological analysis and immunohistochemical staining showed that the wounds treated with CS-A sponges displayed fewer inflammatory cells, and faster regeneration of epithelial tissue, collagen deposition and neovascularization. Therefore, CS-A derivatives have potential application in wound dressings and provide new ideas for the design of multifunctional biomaterials.


Asunto(s)
Adenina/química , Materiales Biocompatibles/química , Quitosano/química , Animales , Vendajes , Materiales Biocompatibles/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Liofilización , Masculino , Ratones , Porosidad , Ratas , Ratas Sprague-Dawley , Piel/efectos de los fármacos , Piel/patología , Cicatrización de Heridas/efectos de los fármacos
8.
Carbohydr Polym ; 260: 117769, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712127

RESUMEN

Periodontal defect poses a significant challenge in orthopedics. Guided Bone Regeneration (GBR) membrane is considered as one of the most successful methods applied to reconstruct alveolar bone and then to achieve periodontal defect repair/regeneration. In this paper, a novel polyamide-6/chitosan@nano-hydroxyapatite/polyamide-6 (PA6/CS@n-HA/PA6) bilayered tissue guided membranes by combining a solvent casting and an electrospinning technique was designed. The developed PA6/CS@n-HA/PA6 composites were characterized by a series of tests. The results show that n-HA/PA6 and electrospun PA6/CS layers are tightly bound by molecular interaction and chemical bonding, which enhances the bonding strength between two distinct layers. The porosity and adsorption average pore diameter of the PA6/CS@n-HA/PA6 membranes are 36.90 % and 22.61 nm, respectively. The tensile strength and elastic modulus of PA6/CS@n-HA/PA6 composites are 1.41 ± 0.18 MPa and 7.15 ± 1.09 MPa, respectively. In vitro cell culture studies demonstrate that PA6/CS@n-HA/PA6 bilayered scaffolds have biological safety, good bioactivity, biocompatibility and osteoconductivity.


Asunto(s)
Regeneración Ósea , Caprolactama/análogos & derivados , Quitosano/química , Durapatita/química , Membranas Artificiales , Nanoestructuras/química , Polímeros/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regeneración Ósea/efectos de los fármacos , Caprolactama/química , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ratones , Nanofibras/química , Nanoestructuras/toxicidad , Porosidad , Propiedades de Superficie , Resistencia a la Tracción
9.
Carbohydr Polym ; 260: 117770, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712128

RESUMEN

Chitin-derived three-dimensional nanomaterials has tremendous potential in pesticide residue analysis as an attractive green substitute for toxic solvents. The work presented herein focuses on constructing the environmentally friendly nitrogen-containing chitin-derived carbon microspheres (N-CCMP) for the efficient adsorption of neonicotinoid pesticides (NPs) including acetamiprid, clothianidin, imidacloprid and thiamethoxam. The N-CCMP displayed hierarchical porous structure, uniform size distribution, and excellent specific surface area of 680.8 m2 g-1. The N-CCMP with N-heterocyclic ring structure and surface oxygen functional groups exhibited good affinity to NPs, which was beneficial for the rapid adsorption. Then, the N-CCMP were utilized as sorbent in extraction of NP residues. Under the optimum conditions, the relative recoveries in water and juice sample were in the range of 85 %-116 % and 74 %-108 %, with relative standard deviations (RSDs) of 0.1 %∼5.2 % and 0.7 %∼5.2 %, respectively. The extraction performance of N-CCMP were still over 80 % after 5 times of reuse.


Asunto(s)
Carbono/química , Quitina/química , Microesferas , Neonicotinoides/química , Nitrógeno/química , Residuos de Plaguicidas/química , Adsorción , Cromatografía Líquida de Alta Presión , Agua Dulce/análisis , Jugos de Frutas y Vegetales/análisis , Neonicotinoides/análisis , Residuos de Plaguicidas/análisis , Porosidad , Espectrometría de Masas en Tándem
10.
Carbohydr Polym ; 260: 117779, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712135

RESUMEN

Task-specific drug release is essential in the development of hydrogels as drug delivery systems. The aim of the study is to report the effect of porosity on alginate hydrogels, which may be controlled by the design of crosslinkers, on drug release behavior. Two alginate-based hydrogels were prepared: alginate-norbornene (Alg-Nb) crosslinked by disulfide-tetrazine (S-Tz; hydrogel A) and alginate-furfuryl amine (Alg-FA) crosslinked by disulfide-maleimide (S-Ma; hydrogel B). Results showed the porosity of hydrogel A was controllable by adjusting the amount of S-Tz. Gel formation was facilitated by a "click" reaction between Alg-Nb and S-Tz, producing nitrogen gas, which, in turn, acted as an in-situ pore generator. Hydrogel B showed a non-porous morphology, as gelation was processed via addition reaction between Alg-FA and S-Ma, which produced no by-product. The study showed that crosslinker proportion and porosity were significant factors influencing drug release behavior of the alginate hydrogels. The presence of a porous structure increased the drug release while non-porous hydrogels led to a very slow release. In addition, the porous alginate hydrogels could sustainably release doxorubicin for 35 days.


Asunto(s)
Alginatos/química , Doxorrubicina/química , Portadores de Fármacos/química , Hidrogeles/química , Disulfuros/química , Doxorrubicina/metabolismo , Liberación de Fármacos , Maleimidas/química , Porosidad
11.
Carbohydr Polym ; 260: 117790, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712138

RESUMEN

A novel approach was introduced to prepare very low density, highly porous, economic, reusable, hydrophobic, and magnetic cellulose aerogels from hardwood dissolving pulp via a simple freeze-drying procedure. The aerogels showed outstanding adsorption efficiency for several oils and organic solvents and demonstrated excellent selectivity for absorbing oil from an oil/water mixture. Moreover, they were easily collected by an external magnet, indicating excellent recyclability and reusable for at least 10 cycles while still retaining supreme adsorption capacity (up to 181 g/g for silicone oil). This study proposes an economic and novel method for the large-scale preparation of hydrophobic and magnetic cellulose aerogels, making them a promising candidate for the efficient and sustainable cleaning of oils and chemical spills.


Asunto(s)
Celulosa/química , Geles/química , Magnetismo , Adsorción , Interacciones Hidrofóbicas e Hidrofílicas , Aceites/química , Porosidad , Reciclaje , Propiedades de Superficie , Contaminantes Químicos del Agua/química
12.
Water Res ; 196: 117016, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33735622

RESUMEN

The transport of microplastics in porous media is attracting increasing attention. However, to date, research is limited to polystyrene microplastics. Meanwhile, surfactants can promote solid dispersion to form a stable suspension, possibly allowing microplastics to migrate when attached to a surfactant, which would increase the scope and degree of microplastic pollution, further endangering human health and the stability of the ecological environment. Therefore, in this study, the transport behavior of microplastics in porous media was explored in the presence of surfactants. Herein, polyethylene (PE) and polypropylene (PP) were evaluated while dispersed by two ionic surfactants: cationic surfactant-cetyltrimethylammonium bromide (CTAB) and anionic surfactant-sodium dodecylbenzenesulfonate (SDBS). The influence of different factors (surfactant concentration, ionic strength, pH, flow rate, and multivalent cations) on the transport of microplastics in porous media was explored via quartz sand packed-column experiments. Our experimental results show that the transport abilities of PE and PP increased with increasing surfactant concentration when the surfactant concentration was less than the critical micelle concentration (CMC). In the presence of CTAB and SDBS, physicochemical factors had different effects on the transport of microplastics mainly by controlling Zeta potential, advection diffusion and CMC. The mobility of PE and PP decreased with increasing ionic strength, cation valence and pH, and decreasing flow rate. However, the mobility of PE and PP under CTAB is much greater than that of PE and PP under SDBS, because quartz sand can absorb more CTAB molecules through electrostatic attraction to weaken the collision between microplastics and quartz sand. Further, the transport ability of PP was greater than that of PE under all conditions considered. Notably, the Extended-Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory formed by adding osmotic, elastic, and hydrophobic force could well described the migration behavior of microplastics in CTAB and SDBS well. This research highlights that surfactant has a significant impact on the transport ability of microplastics, and provides a comprehensive understanding of the migration and fate behaviors of microplastics affected by surfactants, which is necessary to prevent and reduce the environmental hazards of microplastics.


Asunto(s)
Microplásticos , Tensoactivos , Humanos , Plásticos , Polietileno , Polipropilenos , Porosidad
13.
J Environ Manage ; 287: 112360, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33752053

RESUMEN

Water quality plays a central role in the well-being of all the living organisms on planet Earth. The ever-increasing human population and consequently increasing industrialization, urbanization, and chemically boosted cultivation are rapidly contaminating already stressed water resources. The availability of clean drinking water has become scarce for masses across the globe, and this situation is becoming alarming in developing countries. Therefore, the immediate need for cost-effective, easily accessible, eco-friendly, portable, thermally efficient, and chemically stable technologies and materials is desperately felt to meet the high global demand for clean water. To search for effective materials for wastewater treatment, the hyper-cross-linked porous polymers (HCPs) have emerged as an excellent class of porous materials for wastewater treatment due to their unique features of high surface area, tunability, biodegradability, and chemical versatility. This review describes the advances in fabrication strategies and the efficient utilization of hyper-cross-linked porous polymers for wastewater treatment. Moreover, this review specifically discusses the hyper-cross-linked porous polymers effectiveness for the separation of the dyes, nutrients, inorganic ions, organic contaminants, and toxic metals ions. Finally, the review provides insight into the challenges and prospects in the area of hyper-cross-linked porous polymers. Overall, the hyper-cross-linked porous polymers with empowering proper functionalization can provide an opportunity for the wastewater treatment not only to remove toxic contaminants but also to make contaminated water useful for various applications.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Adsorción , Colorantes , Humanos , Iones , Polímeros , Porosidad , Aguas Residuales
14.
Food Chem ; 351: 129316, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33647701

RESUMEN

This study aimed to understand how the microstructure of gelled foods impacts the diffusion of a volatile antimicrobial compound and its efficacy at different depths from the surface. Carvacrol-loaded polylactic acid film was used to inhibit the growth of Pseudomonas fluorescens in WPI-carrageenan gels during storage at 4 °C. The diffusion of antimicrobials was increased in gels having larger average pore size. The antimicrobial efficacy of the antimicrobial packaging was dependent on the diffusion of carvacrol within the gels. The final concentration of carvacrol in the top layer was more than 4 fold higher than that in the middle layer and more than 13-fold higher than that in the bottom layer, resulting in a more effective inhibition in the top layer than those in the middle and bottom layers. Our study demonstrates the importance of considering the diffusion of antimicrobials in solid/semi-solid foods in the antimicrobial packaging design.


Asunto(s)
Antiinfecciosos/química , Cimenos/química , Conservación de Alimentos/métodos , Carragenina/química , Difusión , Geles , Porosidad
15.
Int J Nanomedicine ; 16: 2107-2121, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33737808

RESUMEN

Purpose: Although anti-programmed cell death protein 1 antibody (aPD1) immunotherapy and chemotherapy has made much progress in the treatment of melanoma, the efficacy still needs to be further improved. Methods: Cancer treatment has been greatly enhanced by the use of nanotechnology. Cancer cell membrane (CCM)-camouflaged nanoparticles have shown promising potential in tumor therapy due to their excellent homologous-targeting ability, long blood circulation and immune escape. This work presents a biocompatible and tumor acidic environmental responsive CCM-camouflaged mesoporous silica nanoparticle (CMSN) that is loaded with dacarbazine (DTIC) and combined with aPD1 to achieve better antitumor efficacy. Results: In vitro cell experiments demonstrated that DTIC@CMSN exhibits a better anti-tumor killing efficiency and a stronger ability to promote the apoptosis of tumor cells than free DTIC. In vivo antitumor results demonstrated that combination therapy of DTIC@CMSN chemotherapy and aPD1 immunotherapy remarkably suppress the melanoma growth and prolong survival time due to highly selective tumor killing, activation of tumor-specific T cells, and regulation of the immunosuppressive tumor microenvironment. In addition, safety evaluation studies of DTIC@CMSN also demonstrate their increased tumor accumulation and decreased systemic toxicity. Conclusion: This study provides a promising nano-platform for the combination of chemotherapy with immunotherapy, which is potentially useful for the treatment of melanoma.


Asunto(s)
Antineoplásicos/farmacología , Membrana Celular/patología , Nanopartículas/química , Dióxido de Silicio/química , Microambiente Tumoral/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Terapia Combinada , Dacarbazina/farmacología , Dacarbazina/uso terapéutico , Humanos , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Ratones Endogámicos C57BL , Tamaño de la Partícula , Porosidad , Electricidad Estática
16.
Int J Mol Sci ; 22(4)2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33672949

RESUMEN

Two different types of ordered mesoporous nanoparticles, namely MCM-41 and MCM-48, with similar pore sizes but different pore connectivity, were loaded with aprepitant via a passive diffusion method. The percentage of the loaded active agent, along with the encapsulation efficiency, was evaluated using High-performance Liquid Chromatography (HPLC) analysis complemented by Thermogravimetric Analysis (TGA). The determination of the pore properties of the mesoporous particles before and after the drug loading revealed the presence of confined aprepitant in the pore structure of the particles, while Powder X-ray Diffractometry(pXRD), Differential Scanning Calorimetry (DSC), and FTIR experiments indicated that the drug is in an amorphous state. The release profiles of the drug from the two different mesoporous materials were studied in various release media and revealed an aprepitant release up to 45% when sink conditions are applied. The cytocompatibility of the silica nanoparticles was assessed in Caco-2 cell monolayers, in the presence and absence of the active agent, suggesting that they can be used as carriers of aprepitant without presenting any toxicity in vitro.


Asunto(s)
Aprepitant/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Dióxido de Silicio/química , Administración Oral , Antieméticos/administración & dosificación , Antieméticos/farmacocinética , Aprepitant/farmacocinética , Células CACO-2 , Rastreo Diferencial de Calorimetría , Cromatografía Líquida de Alta Presión , Difusión , Liberación de Fármacos , Humanos , Microscopía Electrónica de Rastreo , Nanopartículas/ultraestructura , Tamaño de la Partícula , Porosidad , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier
17.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33669098

RESUMEN

Thermal energy storage is a technique that has the potential to contribute to future energy grids to reduce fluctuations in supply from renewable energy sources. The principle of energy storage is to drive an endothermic phase change when excess energy is available and to allow the phase change to reverse and release heat when energy demand exceeds supply. Unwanted charge leakage and low heat transfer rates can limit the effectiveness of the units, but both of these problems can be mitigated by incorporating a metal foam into the design of the storage unit. This study demonstrates the benefits of adding copper foam into a thermal energy storage unit based on capric acid enhanced by copper nanoparticles. The volume fraction of nanoparticles and the location and porosity of the foam were optimized using the Taguchi approach to minimize the charge leakage expected from simulations. Placing the foam layer at the bottom of the unit with the maximum possible height and minimum porosity led to the lowest charge time. The optimum concentration of nanoparticles was found to be 4 vol.%, while the maximu possible concentration was 6 vol.%. The use of an optimized design of the enclosure and the optimum fraction of nanoparticles led to a predicted charging time for the unit that was approximately 58% shorter than that of the worst design. A sensitivity analysis shows that the height of the foam layer and its porosity are the dominant variables, and the location of the porous layer and volume fraction of nanoparticles are of secondary importance. Therefore, a well-designed location and size of a metal foam layer could be used to improve the charging speed of thermal energy storage units significantly. In such designs, the porosity and the placement-location of the foam should be considered more strongly than other factors.


Asunto(s)
Cobre/química , Ácidos Decanoicos/química , Nanopartículas/química , Temperatura , Tamaño de la Partícula , Transición de Fase , Porosidad , Propiedades de Superficie
18.
Food Chem ; 352: 129367, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33684718

RESUMEN

About 90% of grapefruit in Florida are affected by Huanglongbing (HLB). HLB negatively affects the organoleptic properties of grapefruit juice because affected trees overproduce bitter secondary-metabolites, mostly naringin. The objective of this research was to remove naringin from HLB-affected grapefruit juice using microporous-adsorbents and to investigate how debittering affected narirutin, limonoids, bergamottin, and consumer acceptability. The adsorption kinetics of naringin on seven adsorbent resins obeyed pseudo-second order. PAD550 and PAD600 showed better static adsorption/desorption. Adsorption-isotherms on these resins were better fitted on Temkin-Pyzhev-model. On a fixed-bed-column packed with PAD550 resin, a slower loading rate increased its breakthrough volume before naringin in effluent reached its taste-threshold. In addition to naringin being reduced to below its taste-threshold, debittering significantly decreased the content of limonin, nomilin, and bergamottin. A consumer taste panel rated debittered and half-debittered juices higher for overall acceptability than the untreated. The half-debittered juice was ranked the most preferred while untreated was the least preferred.


Asunto(s)
Citrus paradisi/química , Citrus paradisi/microbiología , Jugos de Frutas y Vegetales/análisis , Furocumarinas/análisis , Enfermedades de las Plantas/microbiología , Resinas Sintéticas/química , Gusto , Porosidad
19.
Carbohydr Polym ; 260: 117812, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712157

RESUMEN

A dual pH-/thermo-responsive hydrogel was designed based on a polyelectrolyte complex of polyacrylic acid (PAA) and norbornene-functionalized chitosan (CsNb), which was synergized with chemical crosslinking using bistetrazine-poly(N-isopropyl acrylamide) (bisTz-PNIPAM). The thermo-responsive polymeric crosslinker, bisTz-PNIPAM, was synthesized via reversible addition-fragmentation transfer polymerization of NIPAM. FTIR, XRD, rheological and morphological analyses demonstrated the successful formation of the polyelectrolyte network. The highly porous structure generated through the in-situ "click" reaction between Tz and Nb resulted in a higher drug loading (29.35 %). The hydrogel (COOH/NH2 mole ratio of 3:1) exhibited limited drug release (8.5 %) of 5-ASA at a pH of 2.2, but it provided an almost complete release (92 %) at pH 7.4 and 37 °C within 48 h due to the pH responsiveness of PAA, hydrogel porosity, and shrinkage behavior of PNIPAM. The hydrogels were biodegradable and non-toxic against human fibroblast cells, suggesting their considerable potential for a colon-targeted drug delivery system.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Hidrogeles/química , Resinas Acrílicas/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Química Clic , Portadores de Fármacos/toxicidad , Liberación de Fármacos , Humanos , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno , Mesalamina/química , Mesalamina/metabolismo , Porosidad , Temperatura
20.
Carbohydr Polym ; 260: 117840, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712175

RESUMEN

Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe3O4 nanoparticles and a porous nickel layer. This unique structure caused a "multiple reflection-absorb-reflection" process when the electromagnetic waves penetrated the sample. The EMI absorption (SEA) and total SE (SET) increased with Fe3O4 absorption time increasing at 8.2-12.4 GHz, which was attributed to the synergistic effect between porous nickel layer and Fe3O4 nanoparticles. The SEA and SET of the sample with a thickness of 0.195 mm can achieved 18.57 and 41.88 dB, respectively. The design was conducive to improving the magnetic and corrosion resistance properties. This study provided a novel path to obtain a low cost and lightweight electromagnetic shielding material that can reduce secondary radiation.


Asunto(s)
Celulosa/química , Óxido Ferrosoférrico/química , Níquel/química , Protectores contra Radiación/química , Conductividad Eléctrica , Campos Electromagnéticos , Magnetismo , Nanopartículas del Metal/química , Porosidad , Propiedades de Superficie , Temperatura
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