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1.
ACS Omega ; 9(16): 17808-17816, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680301

RESUMO

To progress the clean hydrogen-gas-based energy economy, there is a demand for cost-effective, highly efficient catalysts to facilitate the hydrogen evolution reaction process (HER). Due to the amazing catalytic capabilities of two-dimensional materials, extensive research has been done on these structures. However, most of the described syntheses take a lot of time, are challenging, and are ineffective. The present work demonstrates the performance of the recently reported nanodiamond/graphene composite microsphere ND-GCSs as a catalyst for HER. These spheres were produced via the microwave-irradiation approach. A modified process was adopted to improve the particle size uniformity and yield. The prepared composite spheres showed very interesting catalytic activity for the HER when assembled on a screen-printed carbon electrode. The prepared ND-GCSs@SPCE showed a significant shift of the onset potential to ca. -450 mV and a small Tafel slope value of ca. 85 mV/decade. The electron transfer was drastically enhanced with a tremendous decrease in charge transfer resistance to ca. 265 Ω. The electrocatalyst showed excellent long-term stability for the HER application. Additionally, this novel composite structure might be beneficial for diverse applications including batteries, supercapacitors, catalyst supports, and more.

2.
RSC Adv ; 13(37): 26169-26178, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37664212

RESUMO

Recently, the ultrafine 2D structured nanocomposite of graphene (Gr)-nanodiamonds (NDs) produced by a microwave-assisted chemical route was found to have attractive structural properties. This new 2D structured nanocomposite may be employed for a wide spectrum of applications including thermoelectricity (TE) applications. It is well established that TE materials should be highly effective to be used for designing operative devices for powering or cooling small devices. To fulfill such an objective, the functional TE material should possess a high-power factor and low thermal conductivity. In this study, NDs were successfully integrated into Gr with a magnificent structural alteration to the Gr layers/sheets. This structural modification was found to impact the TE final outcome above and below room temperature (RT). The obtained results showed that at 215 K the power factor value was increased from 4 µW m-1 K-2 for the pure Gr to ∼20 µW m-1 K-2 for the Gr-NDs nanocomposite. At higher T, e.g. 365 K, these values slightly decreased, but with clear superiority for the Gr-NDs nanocomposite. The thermal conductivity of the Gr-NDs nanocomposite was significantly reduced to ∼12% of that of the pure Gr, which could reflect a significant enhancement in the value of the figure of merit by >45 times. Furthermore, the output power generated by a single small leg module made of the Gr-NDs nanocomposite was measured and found to be measurable. The obtained values are still relatively low for practical application, but this newly produced material has great potential to be further developed for TE applications.

3.
Nanomaterials (Basel) ; 13(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36839150

RESUMO

Recently, the n-type TiS2/organic hybrid superlattice (TOS) was found to have efficient thermoelectric (TE) properties above and near room temperature (RT). However, its TE performance and power generation at the temperature gradient below RT have not yet been reported. In this work, the TE performance and power generation of the TOS above and below RT were investigated. The electrical conductivity (σ) and Seebeck coefficient (S) were recorded as a function of temperature within the range 233-323 K. The generated power at temperature gradients above (at ΔT = 20 and 40 K) and below (at ΔT = -20 and -40 K) RT was measured. The recorded σ decreased by heating the TOS, while |S| increased. The resulting power factor recorded ~100 µW/mK2 at T = 233 K with a slight increase following heating. The charge carrier density and Hall mobility of the TOS showed opposite trends. The first factor significantly decreased after heating, while the second one increased. The TE-generated power of a single small module made of the TOS at ΔT = 20 and 40 K recorded 10 and 45 nW, respectively. Surprisingly, the generated power below RT is several times higher than that generated above RT. It reached 140 and 350 nW at ΔT = -20 and -40 K, respectively. These remarkable results indicate that TOS might be appropriate for generating TE power in cold environments below RT. Similar TE performances were recorded from both TOS films deposited on solid glass and flexible polymer, indicating TOS pertinence for flexible TE devices.

4.
ACS Omega ; 8(1): 747-760, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643426

RESUMO

Heavy-oil fly ash (HOFA) is a graphitic carbon powder extracted in vast amounts as a waste material from burning crude oil in power plants. This HOFA has attractive structural properties besides its high amount of pure carbon (∼90 wt %). This powder exists in spherical, highly porous micron-sized particles, which implies its great potential as a mechanical reinforcement for different polymers. In this work, HOFA has been utilized to enhance the mechanical properties of epoxy flooring at HOFA weight fractions of 0, 1, 1.6, and 3.2 wt %. The obtained results revealed that the prepared epoxy-flooring/HOFA composites at a HOFA content of 1.6 wt % showed significant mechanical improvements compared with the pristine polymer. The tensile strength and Young's module values were enhanced by ∼17 and 11%, respectively. Furthermore, the neutron-shielding performance was investigated. The composite with 1.6 wt % showed better neutron attenuation and lower transmittance than the pristine epoxy. The chemical resistance was also extensively studied against sodium hydroxide, nitric acid, and sulfuric acid. The changes in morphology, chemical elements, mass, volume, and molecular structures were investigated rigorously for pristine epoxy and its composite with HOFA at 1.6 wt %. After exposure to these chemicals for 21 days, the tested properties of the epoxy-flooring/HOFA composite showed better chemical resistance than that of the pristine epoxy. Where the epoxy-flooring/HOFA composite showed a surface with low cracks and blistering, it showed lesser changes in mass and volume and fewer molecular structure changes. These results indicated that it is possible to use this multifunctional composite for several applications, including the petrochemical industry, radiation shielding, construction, and automobiles.

5.
Acta Trop ; 237: 106735, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36341780

RESUMO

Two environmental problems exist in some tropical and subtropical areas: the Aedes aegypti (L.) (Ae. aegypti) mosquito and thousands of tons of heavy oil fly ash (HOFA) from power plants. Herein, micro/nanoparticles of HOFA have been utilized as a larvicide against Ae. aegypti without any chemical or biological additive materials. We estimated the accumulative mortalities in the third instar after 24/48 h (h). We found that after 24 h of exposing the larvae to the HOFA microsized, the LC50 and LC90 were 0.55 and 4.87 mg/ml, respectively, while they were 0.10 and 0.36 mg/ml after 48 h. At the same time, the LC50 and LC90 were respectively 0.12 and 0.60 mg/ml after 24 h exposing the larvae to the HOFA nanosized, and they were 0.06 and 0.23 mg/ml after 48 h. These results showed that the HOFA nanoparticles as larvicides were more effective than HOFA microparticles. The microscopy images also revealed deformations such as pigmentations, segment shrinkage, larva swelling, segment body contraction, siphon swelling, intermediate stage, head deformations, and thorax swelling in the larvae exposed to the HOFA. These deformations could indicate alterations in the hormones that control the biochemistry of the larvae body. The findings of this study could suggest the possibility of using HOFA, particularly in nanosized, as a promising larvicide against the Ae. aegypti mosquito.


Assuntos
Aedes , Inseticidas , Animais , Cinza de Carvão/farmacologia , Inseticidas/farmacologia , Folhas de Planta , Extratos Vegetais/farmacologia , Larva
6.
J Funct Biomater ; 13(4)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36412859

RESUMO

Numerous studies have been reported on single- and multicolored highly fluorescent carbon nanoparticles (FCNPs) originating from various sources and their potential applications in bioimaging. Herein, multicolored biocompatible carbon nanoparticles (CNPs) unsheathed from date palm fronds were studied. The extracted CNPs were characterized via several microscopic and spectroscopic techniques. The results revealed that the CNPs were crystalline graphitic and hydrophilic in nature with sizes ranging from 4 to 20 nm. The unsheathed CNPs showed exemplary photoluminescent (PL) properties. They also emitted bright blue colors when exposed to ultraviolet (UV) light. Furthermore, in vitro cellular uptake and cell viability in the presence of CNPs were also investigated. The cell viability of human colon cancer (HCT-116) and breast adenocarcinoma (MCF-7) cell lines with aqueous CNPs at different concentrations was assessed by a cell metabolic activity assay (MTT) for 24 and 48 h incubations. The results were combined to generate dose-response curves for the CNPs and evaluate the severity of their toxicity. The CNPs showed adequate fluorescence with high cell viability for in vitro cell imaging. Under the laser-scanning confocal microscope, the CNPs with HCT-116 and MCF-7 cell lines showed multicolor fluorescence emissions, including blue, green, and red colors when excited at 405, 458, and 561 nm, respectively. These results prove that unsheathed CNPs from date palm fronds can be used in diverse biomedical applications because of their low cytotoxicity, adequate fluorescence, eco-friendly nature, and cheap production.

7.
RSC Adv ; 12(42): 27131-27144, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36276042

RESUMO

Although tris(8-hydroxyquinoline)aluminum (Alq3), a fluorescent optical organometallic material, is known for its applications in optoelectronics, it has only few and limited applications in the biological field. In this study, the antibacterial activity of Alq3 micro and nanostructures was investigated. We prepared Alq3 nanostructures. We prepared nanosized Alq3 as rice-like structures that assembled into flower shapes with an α-crystal phase. Then, Alq3 micro and nanostructure antibacterial activities were estimated against seven human pathogenic bacterial strains. Besides, we compared their antibacterial activities with those of standard antibiotics. The minimal inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and IC50 were evaluated. Alq3 micro and nanostructure antibacterial activity showed considerable values compared to standard antibiotics. Besides, the obtained data revealed that the antibacterial activity of Alq3 in nanostructures with a new morphology is more than that in microstructures. The antibacterial activity of Alq3 nanostructures was attributed to their more surface interactions with the bacterial cell wall. The molecules of 8-hydroxyquinoline in the Alq3 structure could play crucial roles in its antibacterial activity. To apply the achieved results, Alq3 was incorporated with polystyrene (PS) in a ratio of 2% to fabricate a PS/Alq3 composite and used to coat glass beakers, which showed inhibition in the bacterial growth reduced to 65% compared with non-coated beakers. The finding of this study showed that Alq3 could be used as a promising antimicrobial coating.

8.
RSC Adv ; 12(42): 27411-27420, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36276045

RESUMO

Several studies have reported the synthesis of carbon nanoparticles (CNPs) by various methods. In this study, an easy one-step process to unsheathe CNPs from date palm fronds through a top-down ball milling method has been reported. The CNPs were characterized using various spectroscopic and microscopic methods to determine their structural and morphological features, optical properties, crystallinity, physicochemical properties, and particle stability. Transmission electron microscopy (TEM) revealed that the obtained CNPs' size ranged from 4 to 22 nm in a crystalline form. Scanning electron microscopy (SEM) confirmed their spherical shape, while the maximum photoluminescence (PL) intensity was recorded at 464 nm when excited at 375 nm. The unsheathed CNPs produced a good quantum yield (QY) of 3.24%. Furthermore, the CNPs exhibited high Raman ratios of I D/I G and I 2D/I G with values of 0.59 and 0.04, respectively, verifying their multilayer crystalline graphitic nature. These Raman ratios also agree with the X-ray diffractometry (XRD) results. The CNPs' sp2 and sp3 carbon bonds were confirmed by X-ray photoelectron spectroscopy (XPS), with oxygen on the surface forming carboxyl and carbonyl groups with no other observable impurities. Furthermore, the extracted CNPs showed excellent PL properties for up- and down-conversion. These properties are exemplary for low-cost biomass with potential applications in biomedicine. Therefore, the extracted CNPs reported in this study have potential applications in optical imaging.

10.
Nanomaterials (Basel) ; 12(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35957013

RESUMO

Polypyrrole (PPy) is a conducting polymer with attractive thermoelectric (TE) properties. It is simple to fabricate and modify its morphology for enhanced electrical conductivity. However, such improvement is still limited to considerably enhancing TE performance. In this case, a single-wall carbon nanotube (SWCNT), which has ultrathin diameters and exhibits semi-metallic electrical conductivity, might be a proper candidate to be combined with PPy as a core shell one-dimensional (1D) nanocomposite for higher TE power generation. In this work, core shell nanocomposites based on SWCNT/PPy were fabricated. Various amounts of pyrrole (Py), which are monomer sources for PPy, were coated on SWCNT, along with methyl orange (MO) as a surfactant and ferric chloride as an initiator. The optimum value of Py for maximum TE performance was determined. The results showed that the SWCNT acted as a core template to direct the self-assembly of PPy and also to further enhance TE performance. The TE power factor, PF, and figure of merit, zT, values of the pure PPy were initially recorded as ~1 µW/mK2 and 0.0011, respectively. These values were greatly increased to 360 µW/mK2 and 0.09 for the optimized core shell nanocomposite sample. The TE power generation characteristics of the fabricated single-leg module of the optimized sample were also investigated and confirmed these findings. This enhancement was attributed to the uniform coating and good interaction between PPy polymer chains and walls of the SWCNT through π-π stacking. The significant enhancement in the TE performance of SWCNT/PPy nanocomposite is found to be superior compared to those reported in similar composites, which indicates that this nanocomposite is a suitable and scalable TE material for TE power generation.

11.
Polymers (Basel) ; 14(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35808690

RESUMO

Three-dimensional (3D) printing is one of the most futuristic manufacturing technologies, allowing on-demand manufacturing of products with highly complex geometries and tunable material properties. Among the different 3D-printing technologies, fused deposition modeling (FDM) is the most popular one due to its affordability, adaptability, and pertinency in many areas, including the biomedical field. Yet, only limited amounts of materials are commercially available for FDM, which hampers their application potential. Polybutylene succinate (PBS) is one of the biocompatible and biodegradable thermoplastics that could be subjected to FDM printing for healthcare applications. However, microbial contamination and the formation of biofilms is a critical issue during direct usage of thermoplastics, including PBS. Herein, we developed a composite filament containing polybutylene succinate (PBS) and lignin for FDM printing. Compared to pure PBS, the PBS/lignin composite with 2.5~3.5% lignin showed better printability and antioxidant and antimicrobial properties. We further coated silver/zinc oxide on the printed graft to enhance their antimicrobial performance and obtain the strain-specific antimicrobial activity. We expect that the developed approach can be used in biomedical applications such as patient-specific orthoses.

12.
Polymers (Basel) ; 14(14)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35890666

RESUMO

Freshwater reserves are being polluted every day due to the industrial revolution. Man-made activities have adverse effects upon the ecosystem. It is thus the hour of need to explore newer technologies to save and purify water for the growing human population. Capacitive deionization (CDI) is being considered as an emerging technique for removal of excess ions to produce potable water including desalination. Herein, cost-effective activated carbon incorporated with carbon nanotubes (CNT) was used as a freestanding electrode. Further, the desalination efficiency of the designed electrodes was tuned by varying binder concentration, i.e., polyvinylidene difluoride (PVDF) in the activated carbon powder and CNT mixture. PVDF concentration of 5, 7.5, 10, and 12.5 wt% was selected to optimize the freestanding electrode formation and further applied for desalination of water. PVDF content affected the surface morphology, specific surface area, and functional groups of the freestanding electrodes. Moreover, the electrical conductivity and specific surface area changed with PVDF concentration, which ultimately affected the desalination capacity using the freestanding electrodes. This study paves the way to produce cost effective carbon-based freestanding electrodes for capacitive deionization and other applications including battery electrodes.

13.
Methods ; 199: 37-53, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34543747

RESUMO

Oil fly ash (OFA) is a byproduct generated by the burning of heavy crude oil in factories and power plants. Millions of tons of OFA is produced annually worldwide and is mostly treated as solid waste. Extensive efforts have been made to utilize OFA and reduce its environmental effects. Recently, OFA has been found to be a suitable catalyst and co-precursor for carbon nanotube (CNTs) production. However, the treatment methods used are expensive and time consuming. Here, we describe a new method for OFA treatment and provide optimized growth conditions for CNTs production. Pre-sintering of OFA at elevated temperatures (400-450 °C) in air or vacuum using a chemical vapor deposition (CVD) tube furnace (80-100 min) is a very effective treatment method for CNTs growth under optimum growth conditions. The optimum parameters for CNTs growth were growth temperature, gas pressure, gas flow rate, and growth time. Well-defined, thin nanotubes with diameters of 20-40 nm were produced. Bamboo-like nanotubes with zigzag curved walls were also observed in the produced CNTs. The weight percentage of the produced CNTs was approximately twice that of the treated OFA. Consequently, the pre-sintering method exhibited suitability for the mass production of CNTs. Thus, large quantities of the nanomaterial can be supplied for use in various applications, e.g., polymer composites, the rubber industry, construction materials, and lubricant additives.


Assuntos
Cinza de Carvão , Nanotubos de Carbono , Catálise , Polímeros
14.
Nanomaterials (Basel) ; 11(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34835721

RESUMO

We describe a graphene and fibrous multiwall carbon nanotubes (f-MWCNT) composite film prepared by plasma-enhanced chemical vapor deposition for use as a suitable and possible candidate of hydrogen storage materials. A high storage capacity of 5.53 wt% has been obtained with improved kinetics. The addition of binary PdMg alloy nanoparticles to the surface of graphene-fibrous nanotubes composite films raised the storage capacity by 53% compared to the film without PdMg decorated nanoparticles. Additionally, the graphene/f-MWCNT composite film decorated with PdMg nanoparticles exhibited an enhanced hydrogen absorption-desorption kinetics. The fibrous structure of the MWCNTs, alongside graphene sheets within the film, creates an enormous active region site for hydrogen reaction. The addition of PdMg nanoparticles enhanced the reaction kinetics due to the catalytic nature of Pd, and increased the hydrogen content due to the high absorption capacity of Mg nanoparticles. The combination of Pd and Mg in a binary alloy nanoparticle enhanced the hydrogen capacity and absorption-desorption kinetics.

15.
ACS Appl Mater Interfaces ; 13(22): 26421-26430, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34047542

RESUMO

Graphite has become a critical material because of its essential role in the lithium-ion battery (LIB) industry. However, the synthesis of graphite requires an energy-intensive thermal treatment. Also, when used in sodium-ion and potassium-ion batteries (SIBs and PIBs), the graphite anode shows poor capacities and cycling stability, which hinders the development of next-generation battery technologies. Finding suitable anode materials for commercial alkali metal-ion batteries is not only urgent for the energy storage industry, but is also important for economic and sustainable development. In this work, we use fly ash carbon (FAC), a residue of crude oil combustion, as an anode material for alkali metal-ion batteries. The FAC anodes show relatively high capacities and excellent cycling stability. The charge storage mechanism of FAC anode is shown to be intercalation coupled with redox reactions of oxygen functional groups. This work shows that FAC is a promising scalable anode material for alkali metal-ion batteries.

16.
Acta Biomater ; 127: 313-326, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33705990

RESUMO

Bone defects are commonly caused by traumatic injuries and tumor removal and critically sized defects overwhelm the regenerative capacity of the native tissue. Reparative strategies such as auto, xeno, and allografts have proven to be insufficient to reconstruct and regenerate these defects. For the first time, we introduce the use of handheld melt spun three dimensional printers that can deposit materials directly within the defect site to properly fill the cavity and form free-standing scaffolds. Engineered composite filaments were generated from poly(caprolactone) (PCL) doped with zinc oxide nanoparticles and hydroxyapatite microparticles. The use of PCL-based materials allowed low-temperature printing to avoid overheating of the surrounding tissues. The in situ printed scaffolds showed moderate adhesion to wet bone tissue, which can prevent scaffold dislocation. The printed scaffolds showed to be osteoconductive and supported the osteodifferentiation of mesenchymal stem cells. Biocompatibility of the scaffolds upon in vivo printing subcutaneously in mice showed promising results. STATEMENT OF SIGNIFICANCE.


Assuntos
Impressão Tridimensional , Alicerces Teciduais , Animais , Regeneração Óssea , Osso e Ossos , Durapatita , Camundongos , Osteogênese , Poliésteres , Engenharia Tecidual
17.
Polymers (Basel) ; 13(2)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467017

RESUMO

Conducting polymers have attracted significant attention due to their easy fabrication, morphology modification, and their electrical properties. Amongst them, polypyrrole (PPy) has attractive thermoelectric (TE) properties. Engineering of this polymer in one-dimensional (1D) nanostructured form is found to enhance its TE performance. This was achieved in the present work by using multi-walled carbon nanotubes (MWCNTs) as a core template to direct the self-assembly of PPy and also to further enhance its TE performance. The growth of PPy on the sidewalls of MWCNTs was performed in an acidic medium based oxidative in situ polymerization. Various concentrations of MWCNTs within the range 1.1-14.6 wt.% were used to form the MWCNTs/PPy nanocomposites in 1D core-shell structures. The morphology and microstructure results of the produced nanocomposite samples showed that this MWCNTs were successfully coated by thick and thin layers of PPy. At low concentrations of MWCNTs, thick layers of PPy are formed. While at high concentrations thin layers are coated. The formed 1D nanocomposites have enhanced TE performance, particularly those containing higher contents of MWCNTs. The power factor and figure of merit values for the formed 1D nanocomposites recorded around 0.77 µV/mK2 and 1 × 10-3 at room temperature (RT), respectively. This enhancement was attributed to the perfect coating and good interaction between PPy and MWCNT through π-π stacking between the polymer chains and these nanotubes. These results might be useful for developing future TE materials and devices.

18.
Nanomaterials (Basel) ; 12(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35010069

RESUMO

The demand for supercapacitors has been high during the integration of renewable energy devices into the electrical grid. Although activated carbon materials have been widely utilized as supercapacitor electrodes, the need for economic and sustainable processes to extract and activate carbon nanomaterials is still crucial. In this work, the biomass waste of date palm fronds is converted to a hierarchical porous nanostructure of activated carbon using simple ball-milling and sonication methods. Chemical and physical activation agents of NaOH and CO2, receptively, were applied on two samples separately. Compared with the specific surface area of 603.5 m2/g for the CO2-activated carbon, the NaOH-activated carbon shows a higher specific surface area of 1011 m2/g with a finer nanostructure. Their structural and electrochemical properties are functionalized to enhance electrode-electrolyte contact, ion diffusion, charge accumulation, and redox reactions. Consequently, when used as electrodes in an H2SO4 electrolyte for supercapacitors, the NaOH-activated carbon exhibits an almost two-fold higher specific capacitance (125.9 vs. 56.8 F/g) than that of the CO2-activated carbon at the same current density of 1 A/g. Moreover, using carbon cloth as a current collector provides mechanical flexibility to our electrodes. Our practical approach produces cost-effective, eco-friendly, and flexible activated carbon electrodes with a hierarchical porous nanostructure for supercapacitor applications.

19.
Sci Rep ; 10(1): 20428, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33235239

RESUMO

Non-healing wounds have placed an enormous stress on both patients and healthcare systems worldwide. Severe complications induced by these wounds can lead to limb amputation or even death and urgently require more effective treatments. Electrospun scaffolds have great potential for improving wound healing treatments by providing controlled drug delivery. Previously, we developed fibrous scaffolds from complex carbohydrate polymers [i.e. chitin-lignin (CL) gels]. However, their application was limited by solubility and undesirable burst drug release. Here, a coaxial electrospinning is applied to encapsulate the CL gels with polycaprolactone (PCL). Presence of a PCL shell layer thus provides longer shelf-life for the CL gels in a wet environment and sustainable drug release. Antibiotics loaded into core-shell fibrous platform effectively inhibit both gram-positive and -negative bacteria without inducting observable cytotoxicity. Therefore, PCL coated CL fibrous gel platforms appear to be good candidates for controlled drug release based wound dressing applications.


Assuntos
Antibacterianos/farmacologia , Quitina/química , Lignina/química , Poliésteres/química , Animais , Antibacterianos/química , Bandagens , Cápsulas , Preparações de Ação Retardada , Estabilidade de Medicamentos , Géis/síntese química , Géis/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Cicatrização/efeitos dos fármacos
20.
Integr Cancer Ther ; 18: 1534735419862351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31282195

RESUMO

Background: This study evaluated the cardioprotective effect of Ajwa nano-preparation against doxorubicin-associated cardiotoxicity. Methods: Twenty-four male Wistar rats (200-250 g) were divided into 3 groups. One group was given the nanopreparation containing both Ajwa fruit and pit in a dose of 1.4 g/kg orally 1 hour before doxorubicin infusion (Dates-DOX group). Another group was given the vehicle for 1 hour before doxorubicin infusion (DOX group). The third group received the vehicle but no DOX infusion (time control). Cardiac hemodynamics, blood pressure, cardiac contractility, and conductivity were recorded before and after 45 minutes of infusion of doxorubicin (15 mg/kg, slow intravenous over 45 minutes). Blood samples were collected before and after doxorubicin infusion. Heart tissue samples were collected and snap frozen until assay of reduced glutathione. Results: Rats pre-administered Ajwa nanopreparation were protected from doxorubicin-associated systolic and diastolic dysfunction based on the significant elevation in the rate of rise in left ventricular pressure (dp/dtmax) and (dp/dtmin) compared with the DOX group. In addition, it prevented the doxorubicin-associated ischemia based on the significant shortening in QT interval, JT interval, and Tpeak-Tend interval versus the DOX group. There was no effect on atrial conductivity (PR interval and P duration). Ajwa pretreatment increased the antioxidant capacity of cardiac tissue, as evidenced by increasing the cardiac content of reduced glutathione compared with the untreated doxorubicin group. Conclusion: Ajwa nanopreparation protects from doxorubicin-associated cardiotoxicity through alleviating cardiac ischemia and increasing cardiac antioxidant capacity.


Assuntos
Antioxidantes/metabolismo , Doxorrubicina/efeitos adversos , Cardiopatias/induzido quimicamente , Cardiopatias/tratamento farmacológico , Coração/efeitos dos fármacos , Nanopartículas/administração & dosagem , Preparações de Plantas/farmacologia , Animais , Antibióticos Antineoplásicos/efeitos adversos , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Frutas/química , Glutationa/metabolismo , Cardiopatias/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Phoeniceae/química , Ratos , Ratos Wistar
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