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1.
RSC Adv ; 14(12): 8178-8187, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38469189

RESUMO

Supercapacitors (SCs) have emerged as attractive energy storage devices due to their rapid charge/discharge rates, long cycle life, and high-power density. However, the development of innovative electrode materials to achieve high-performance remains crucial to meet future requirements in supercapacitor technology. In this work, we have explored the potential of a microwave-engineered NiZrO3@GNP composite as a promising electrode material for SCs. A microwave assisted hydrothermal approach was adopted for the fabrication of the NiZrO3@GNP nanocomposite. Structural and morphological investigations showed its structural richness and its chemical compositions. When applied as a SC electrode, this innovative combination exhibits battery-like behaviour with higher specific capacity (577.63 C g-1) with good cyclic stability, and good performance. We have assembled an asymmetric-type two-electrode SC device and analysed its electrochemical features. This NiZrO3@GNP device exhibits the specific capacity of 47 C g-1 with capacitance retention of 70% after 2000 charge-discharge cycles. Further research on optimizing the synthesis process and exploring different device configurations could pave the way for even higher-performance supercapacitors in the future.

2.
J Funct Biomater ; 15(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38391896

RESUMO

Enhancing nanoparticles' anti-cancer capabilities as drug carriers requires the careful adjustment of formulation parameters, including loading efficiency, drug/carrier ratio, and synthesis method. Small adjustments to these parameters can significantly influence the drug-loading efficiency of nanoparticles. Our study explored how chitosan and polyethylene glycol (PEG) coatings affect the structural properties, drug-loading efficiency, and anti-cancer efficacy of Fe3O4 nanoparticles (NPs). The loading efficiency of the NPs was determined using FTIR spectrometry and XRD. The quantity of chrysin incorporated into the coated NPs was examined using UV-Vis spectrometry. The effect of the NPs on cell viability and apoptosis was determined by employing the HCT 116 human colon carcinoma cell line. We showed that a two-fold increase in drug concentration did not impact the loading efficiency of Fe3O4 NPs coated with PEG. However, there was a 33 Å difference in the crystallite sizes obtained from chitosan-coated Fe3O4 NPs and drug concentrations of 1:0.5 and 1:2, resulting in decreased system stability. In conclusion, PEG coating exhibited a higher loading efficiency of Fe3O4 NPs compared to chitosan, resulting in enhanced anti-tumor effects. Furthermore, variations in the loaded amount of chrysin did not impact the crystallinity of PEG-coated NPs, emphasizing the stability and regularity of the system.

3.
RSC Adv ; 14(5): 3209-3231, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38249671

RESUMO

Laminarin, a complicated polysaccharide originating from brown algae, has emerged as a compelling candidate in the domain of biomedical research. This enigmatic molecule, composed of glucose units associated with both ß-1,3 and ß-1,6 glycosidic bonds, possesses an array of remarkable characteristics that render it auspicious for multifaceted biomedical applications. This review investigates the comprehensive potential of laminarin in the biomedical domain, emphasizing its remarkable biocompatibility, low cytotoxicity, and cell proliferation support. Laminarin's immunomodulatory attributes position it as an encouraging contender in immunotherapy and the development of vaccines. Moreover, its anti-inflammatory and antioxidant characteristics provide a promising avenue for combatting conditions associated with oxidative stress. In particular, laminarin excels as a drug delivery vehicle owing to its exceptional encapsulation capabilities emerging from its porous framework. Integrating pH and redox responsiveness in laminarin-based drug delivery systems is poised to redefine targeted therapies. Laminarin substantially contributes to tissue engineering by improving adhesion, migration of cells, and deposition of extracellular matrix. This augmentation magnifies the regenerative capability of tissue-engineered constructs, substantiated by the advancement of laminarin-based wound dressings and tissue scaffolds, marking considerable progress in the domain of wound healing and tissue regeneration. While laminarin exhibits substantial potential in biomedical applications, it remains in the initial phases of exploration. Comprehensive preclinical and clinical research is warranted to verify its effectiveness and safety across various applications. In essence, laminarin, a marine marvel, has the capability to remodel biomedical research, offering inventive solutions to complex difficulties.

4.
Molecules ; 28(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067437

RESUMO

(1) Background: DA-Gelucire® 50/13-based solid lipid nanoparticles (SLNs) administering the neurotransmitter dopamine (DA) and the antioxidant grape-seed-derived proanthocyanidins (grape seed extract, GSE) have been prepared by us in view of a possible application for Parkinson's disease (PD) treatment. To develop powders constituted by such SLNs for nasal administration, herein, two different agents, namely sucrose and methyl-ß-cyclodextrin (Me-ß-CD), were evaluated as cryoprotectants. (2) Methods: SLNs were prepared following the melt homogenization method, and their physicochemical features were investigated by Raman spectroscopy, Scanning Electron Microscopy (SEM), atomic force microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). (3) Results: SLN size and zeta potential values changed according to the type of cryoprotectant and the morphological features investigated by SEM showed that the SLN samples after lyophilization appear as folded sheets with rough surfaces. On the other hand, the AFM visualization of the SLNs showed that their morphology consists of round-shaped particles before and after freeze-drying. XPS showed that when sucrose or Me-ß-CD were not detected on the surface (because they were not allocated on the surface or completely absent in the formulation), then a DA surfacing was observed. In vitro release studies in Simulated Nasal Fluid evidenced that DA release, but not the GSE one, occurred from all the cryoprotected formulations. Finally, sucrose increased the physical stability of SLNs better than Me-ß-CD, whereas RPMI 2650 cell viability was unaffected by SLN-sucrose and slightly reduced by SLN-Me-ß-CD. (4) Conclusions: Sucrose can be considered a promising excipient, eliciting cryoprotection of the investigated SLNs, leading to a powder nasal pharmaceutical dosage form suitable to be handled by PD patients.


Assuntos
Extrato de Sementes de Uva , Nanopartículas , Humanos , Extrato de Sementes de Uva/farmacologia , Dopamina , Pós , Nanopartículas/química , Crioprotetores , Liofilização/métodos , Sacarose/química , Tamanho da Partícula
5.
J Funct Biomater ; 14(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38132812

RESUMO

The synthesis of graphene-based materials for drug delivery represents an area of active research, and the use of graphene in drug delivery systems is promising due to its unique properties. Thus, in the present work, we discuss the potential of few-layer graphene in a hydrogel system for dopamine release. The hydrogels are frequently used for these systems for their special physico-chemical properties, which can ensure that the drug is effectively released in time. However, the release from such structures is mostly determined by diffusion alone, and to overcome this restriction, the hydrogel can be "improved" with nanoscale fillers like graphene. The release kinetics of the composite obtained were analyzed to better understand how the use of graphene, instead of the more common graphene oxide (GO) and reduced graphene oxide (rGO), affects the characteristics of the system. Thus, the systems developed in this study consist of three main components: biopolymer, graphene, and dopamine. The hydrogels with graphene were prepared by combining two different solutions, one with polyacrylic acid and agarose and one with graphene prepared by the exfoliation method with microwave irradiation. The drug delivery systems were developed by adding dopamine to the obtained hydrogels. After 24 h of release, the presence of dopamine was observed, demonstrating that the system developed can slow down the drug's degradation because of the interactions with the graphene nanoplates and the polymer matrix.

6.
Front Chem ; 11: 1267199, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720717

RESUMO

Wide bandgap oxidized graphenes have garnered particular interest among the materials explored for these applications because of their exceptional semiconducting and optical properties. This study aims to investigate the tunability of the related properties in reduced graphene oxide (rGO) for potential use in energy conversion, storage, and optoelectronic devices. To accomplish this, we scrutinized crucial parameters of the synthesis process such as reduction time and temperature. Our findings demonstrate that controlling these parameters makes it possible to customize the optical bandgap of reduced graphene oxide within a range of roughly 2.2 eV-1.6 eV. Additionally, we observed that reduced graphene oxide has strong and superior absorption in the visible region, which is attributable to the existence of OFGs and defects. Notably, our results indicate that the absorption coefficients of reduced graphene oxide are up to almost three times higher (7426 ml mg-1 m-1) than those observed in dispersions of exfoliated graphene and graphene oxide (GO). To complement our findings, we employed several spectroscopic and morphological characterizations, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and electrical measurements. The implications of our results are significant for the development and design of future semiconductors for energy conversion and optoelectronic applications.

7.
Materials (Basel) ; 16(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37570131

RESUMO

Following some previous work by some of us on the second order nonlinear optical (NLO) properties of Zn(II) meso-tetraphenylporphyrin (ZnP), fullerene, and ferrocene (Fc) diads and triads, in the present research, we explore the NLO response of some new hybrids with two-dimensional graphene nanoplates (GNP) instead of a zero-dimensional fullerene moiety as the acceptor unit. The experimental data, collected by Electric Field Induced Second Harmonic generation (EFISH) technique in CH2Cl2 solution with a 1907 nm incident wavelength, combined with Coupled-Perturbed (CP) and Finite Field (FF) Density Functional Theory (DFT) calculations, show a strongly enhanced contribution of the cubic electronic term γ(-2ω; ω, ω, 0), due to the extended π-conjugation of the carbonaceous acceptor moiety.

8.
Nanomaterials (Basel) ; 13(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37570581

RESUMO

In this study, we investigate how changing important synthesis-related parameters can affect and control the optical characteristics of graphene oxide (GO) and reduced graphene oxide (rGO). These parameters include drying time and reduction time at two different temperatures. We obtain an understanding of their impact on optical transitions, optical bandgap, absorption coefficient, and absorbance spectrum width by analyzing these factors. Accordingly, GO has an optical bandgap of about 4 eV, which is decreased by the reduction process to 1.9 eV. Both GO and rGO display greater absorption in the visible spectrum, which improves photon capture and boosts efficiency in energy conversion applications. Additionally, our results show that GO and rGO have higher absorption coefficients than those previously reported for dispersions of exfoliated graphene. Defects in GO and rGO, as well as the presence of functional oxygen groups, are the main contributors to this increased absorption. Several measurements are carried out, including spectroscopic and morphological studies, to further support our findings.

9.
Molecules ; 28(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37570864

RESUMO

Natural bentonite clay (BE) underwent modification steps that involved the exfoliation of its layers into separated nanosheets (EXBE) and further functionalization of these sheets with methanol, forming methoxy-exfoliated bentonite (Mth/EXBE). The synthetically modified products were investigated as enhanced carriers of 5-fluorouracil as compared to raw bentonite. The modification process strongly induced loading properties that increased to 214.4 mg/g (EXBE) and 282.6 mg/g (Mth/EXBE) instead of 124.9 mg/g for bentonite. The loading behaviors were illustrated based on the kinetic (pseudo-first-order model), classic isotherm (Langmuir model), and advanced isotherm modeling (monolayer model of one energy). The Mth/EBE carrier displays significantly higher loading site density (95.9 mg/g) as compared to EXBE (66.2 mg/g) and BE (44.9 mg/g). The loading numbers of 5-Fu in each site of BE, EXBE, and Mth/EXBE (>1) reflect the vertical orientation of these loaded ions involving multi-molecular processes. The loading processes that occurred appeared to be controlled by complex physical and weak chemical mechanisms, considering both Gaussian energy (<8 KJ/mol) as well as loading energy (<40 KJ/mol). The releasing patterns of EXBE and Mth/EXBE exhibit prolonged and continuous properties up to 100 h, with Mth/EXBE displaying much faster behaviors. Based on the release kinetic modeling, the release reactions exhibit non-Fickian transport release properties, validating cooperative diffusion and erosion release mechanisms. The cytotoxicity of 5-Fu is also significantly enhanced by these carriers: 5-Fu/BE (8.6% cell viability), 5-Fu/EXBE (2.21% cell viability), and 5-Fu/Mth/EXBE (0.73% cell viability).


Assuntos
Bentonita , Fluoruracila , Fluoruracila/farmacologia , Fluoruracila/química , Bentonita/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Íons
10.
Sci Total Environ ; 900: 166137, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37595927

RESUMO

This research is devoted to assessing the pollution within a Mediterranean Sea area in the East coast of Algeria, which is known for its port and industrial activities. This study aims to assess the health status of the Gulf of Annaba located in the extreme North-East of Algeria by examining the contamination level by trace elements (Cu, Zn, Pb, Cd, Hg) in the sediments and muscles of Mugil cephalus fish. The obtained results manifest significant variations in metal levels in the sediments throughout the stations and the sampling seasons. The contamination by (Zn, Cu, Pb, Cd) of Joannonville and Sidi Salem stations is observed during both seasons whereas at the Chapuis station occurs only during the summer. The contamination indices are higher than 3, hence classifying the sediments of these three stations as "sediments at risk". Joannonville station manifests high levels of Hg only during the summer. For the muscles of M. cephalus, the contamination levels are found to be dependent on the species and the studied station. The fish inhabiting Joannonville and Sidi Salem show higher levels of (Zn, Pb, Cd) compared to the FAO/WHO standards, whereas the Pb level at Chapuis exceeds the standard during summer. Accordingly, the consumption of fish from Joannonville, Sidi Salem and Chapuis stations presents a serious threat regarding the toxicological risks based on the observed levels of contamination.


Assuntos
Mercúrio , Smegmamorpha , Oligoelementos , Animais , Estações do Ano , Argélia , Cádmio , Chumbo , Peixes
11.
Front Chem ; 11: 1214072, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547907

RESUMO

The study of the optical properties of graphene oxide (GO) is crucial in designing functionalized GO materials with specific optical properties for various applications such as (bio) sensors, optoelectronics, and energy storage. The present work aims to investigate the electronic transitions, optical bandgap, and absorption coefficient of GO under different conditions. Specifically, the study examines the effects of drying times ranging from 0 to 120 h while maintaining a fixed temperature of 80°C and low temperatures ranging from 40℃ to 100℃, with a constant drying time of 24 h. Our findings indicate that exposing the GO sample to a drying time of up to 120 h at 80°C can lead to a reduction in the optical bandgap, decreasing it from 4.09 to 2.76 eV. The π-π* transition was found to be the most affected, shifting from approximately 230 nm at 0 h to 244 nm after 120 h of drying time. Absorption coefficients of 3140-5507 ml mg-1 m-1 were measured, which are similar to those reported for exfoliated graphene dispersions but up to two times higher, confirming the improved optical properties of GO. Our findings can provide insights into determining the optimal temperature and duration required for transforming GO into its reduced form for a specific application through extrapolation. The study is complemented by analyzing the elemental composition, surface morphology change, and electrical properties.

12.
Materials (Basel) ; 16(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37512232

RESUMO

Natural kaolinite was subjected to a successful exfoliation process into separated kaolinite nanosheets (KNs), followed by hybridization with ß-cyclodextrin biopolymer (ß-CD), forming an advanced bio-nanocomposite (ß-CD/KNs). The synthetic products were evaluated as enhanced delivery structures for oxaliplatin chemotherapy (OXAPN). The hybridization of KNs with ß-CD polymer notably enhanced the loading capacity to 355.3 mg/g (ß-CD/KNs) as compared to 304.9 mg/g for KNs. The loading of OXAPN into both KNs and ß-CD/KNs displayed traditional pseudo-first-order kinetics (R2 > 0.85) and a conventional Langmuir isotherm (R2 = 0.99). The synthetic ß-CD/KNs validates a greater occupied effective site density (98.7 mg/g) than KNs (66.3 mg/g). Furthermore, the values of the n steric parameter (4.7 (KNs) and 3.6 (ß-CD/KNs)) reveal the vertical orientation of the loaded molecules and the loading of them by multi-molecular mechanisms. These mechanisms are mainly physical processes based on the obtained Gaussian energy (<8 KJ/mol) and loading energy (<40 KJ/mol). The release profiles of both KNs and ß-CD/KNs extend for about 120 h, with remarkably faster rates for ß-CD/KNs. According to the release kinetic findings, the release of OXAPN displays non-Fickian transport behavior involving the cooperation of diffusion and erosion mechanisms. The KNs and ß-CD/KNs as free particles showed considerable cytotoxicity and anticancer properties against HCT-116 cancer cell lines (71.4% cell viability (KNs) and 58.83% cell viability (ß-CD/KNs)). Additionally, both KNs and ß-CD/KNs significantly enhanced the OXAPN's cytotoxicity (2.04% cell viability (OXAPN/KNs) and 0.86% cell viability (OXAPN/ß-CD/KNs).

13.
Molecules ; 28(13)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37446820

RESUMO

Natural kaolinite underwent advanced morphological-modification processes that involved exfoliation of its layers into separated single nanosheets (KNs) and scrolled nanoparticles as nanotubes (KNTs). Synthetic nanostructures have been characterized as advanced and effective oxaliplatin-medication (OXAP) delivery systems. The morphological-transformation processes resulted in a remarkable enhancement in the loading capacity to 304.9 mg/g (KNs) and 473 mg/g (KNTs) instead of 29.6 mg/g for raw kaolinite. The loading reactions that occurred by KNs and KNTs displayed classic pseudo-first-order kinetics (R2 > 0.90) and conventional Langmuir isotherms (R2 = 0.99). KNTs exhibit a higher active site density (80.8 mg/g) in comparison to KNs (66.3 mg/g) and raw kaolinite (6.5 mg/g). Furthermore, compared to KNs and raw kaolinite, each site on the surface of KNTs may hold up to six molecules of OXAP (n = 5.8), in comparison with five molecules for KNs. This was accomplished by multi-molecular processes, including physical mechanisms considering both the Gaussian energy (<8 KJ/mol) and the loading energy (<40 KJ/mol). The release activity of OXAP from KNs and KNTs exhibits continuous and regulated profiles up to 100 h, either by KNs or KNTs, with substantially faster characteristics for KNTs. Based on the release kinetic investigations, the release processes have non-Fickian transport-release features, indicating cooperative-diffusion and erosion-release mechanisms. The synthesized structures have a significant cytotoxicity impact on HCT-116 cancer cell lines (KNs (71.4% cell viability and 143.6 g/mL IC-50); KNTs (11.3% cell viability and 114.3 g/mL IC-50). Additionally, these carriers dramatically increase OXAP's cytotoxicity (2.04% cell viability, 15.4 g/mL IC-50 (OXAP/KNs); 0.6% cell viability, 4.5 g/mL IC-50 (OXAP/KNTs)).


Assuntos
Caulim , Nanotubos , Caulim/farmacologia , Caulim/química , Oxaliplatina/farmacologia , Cinética , Preparações Farmacêuticas
14.
Molecules ; 28(14)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37513298

RESUMO

Synthetic zeolite-A (ZA) was hybridized with two different biopolymers (chitosan and ß-cyclodextrin) producing biocompatible chitosan/zeolite-A (CS/ZA) and ß-cyclodextrin/zeolite-A (CD/ZA) biocomposites. The synthetic composites were assessed as bio-carriers of the 5-fluorouracil drug (5-Fu) with enhanced properties, highlighting the impact of the polymer type. The hybridization by the two biopolymers resulted in notable increases in the 5-Fu loading capacities, to 218.2 mg/g (CS/ZA) and 291.3 mg/g (CD/ZA), as compared to ZA (134.2 mg/g). The loading behaviors using ZA as well as CS/ZA and CD/ZA were illustrated based on the classic kinetics properties of pseudo-first-order kinetics (R2 > 0.95) and the traditional Langmuir isotherm (R2 = 0.99). CD/ZA shows a significantly higher active site density (102.7 mg/g) in comparison to CS/ZA (64 mg/g) and ZA (35.8 mg/g). The number of loaded 5-Fu per site of ZA, CS/ZA, and CD/ZA (>1) validates the vertical ordering of the loaded drug ions by multi-molecular processes. These processes are mainly physical mechanisms based on the determined Gaussian energy (<8 kJ/mol) and loading energy (<40 kJ/mol). Both the CS/ZA and CD/ZA 5-Fu release activities display continuous and controlled profiles up to 80 h, with CD/ZA exhibiting much faster release. According to the release kinetics studies, the release processes contain non-Fickian transport release properties, suggesting cooperative diffusion and erosion release mechanisms. The cytotoxicity of 5-Fu is also significantly enhanced by these carriers: 5-Fu/ZA (11.72% cell viability), 5-Fu/CS/ZA (5.43% cell viability), and 5-Fu/CD/ZA (1.83% cell viability).


Assuntos
Antineoplásicos , Quitosana , Zeolitas , beta-Ciclodextrinas , Fluoruracila/farmacologia , Fluoruracila/química , Quitosana/química , Cinética , Portadores de Fármacos/química , beta-Ciclodextrinas/química
15.
Molecules ; 28(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175102

RESUMO

Brown macroalgae (BMG) were used as carriers for ZnO (ZnO/BMG) and cobalt-doped ZnO (Co-ZnO/BMG) via facile microwave-assisted hydrothermal synthesis. The multifunctional structures of synthesized composites were evaluated as enhanced antioxidant and anti-diabetic agents based on the synergistic effects of ZnO, Co-ZnO, and BMG. BMG substrate incorporation and cobalt doping notably enhanced the bioactivity of the synthesized ZnO nanoparticles. As an antioxidant, the Co-ZnO/BMG composite exhibited highly effective scavenging properties for the common free reactive oxygen radicals (DPPH [89.6 ± 1.5%], nitric oxide [90.2 ± 1.3%], ABTS [87.7 ± 1.8%], and O2●- [46.7 ± 1.9%]) as compared to ascorbic acid. Additionally, its anti-diabetic activity was enhanced significantly and strongly inhibited essential oxidative enzymes (porcine α-amylase (90.6 ± 1.5%), crude α-amylase (84.3 ± 1.8%), pancreatic α-glucosidase (95.7 ± 1.4%), crude intestinal α-glucosidase (93.4 ± 1.8%), and amyloglucosidase (96.2 ± 1.4%)). Co-ZnO/BMG inhibitory activity was higher than that of miglitol, and in some cases, higher than or close to that of acarbose. Therefore, the synthetic Co-ZnO/BMG composite can be used as a commercial anti-diabetic and antioxidant agent, considering the cost and adverse side effects of current drugs. The results also demonstrate the impact of cobalt doping and BMG integration on the biological activity of ZnO.


Assuntos
Diabetes Mellitus , Nanopartículas Metálicas , Sargassum , Alga Marinha , Óxido de Zinco , Animais , Suínos , Antioxidantes/farmacologia , Antioxidantes/química , Sargassum/metabolismo , Óxido de Zinco/farmacologia , Óxido de Zinco/química , alfa-Glucosidases , Hipoglicemiantes/farmacologia , alfa-Amilases , Cobalto/química , Nanopartículas Metálicas/química , Alga Marinha/metabolismo
16.
Sci Rep ; 13(1): 8837, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258634

RESUMO

The dependency of CO2 reduction rate in acetonitrile-Bu4NClO4 solution on cathodes, which were modified by laser induction of a copper surface, was studied. The topography of laser-induced periodic surface structures (LIPSS) → grooves → spikes was successively formed by a certain number of pulses. It was proved that for a higher number of laser pulses, the surface area of the copper cathode increases and preferred platy orientation of the copper surface on [022] crystallografic direction and larger fluence values increase. At the same time, the content of copper (I) oxide on the surface of the copper cathode increases. Also, the tendency to larger fluency values is observed. It promotes the increase of cathodic current density for CO2 reduction, which reaches values of 14 mA cm-2 for samples with spikes surface structures at E = - 3.0 V upon a stable process.

17.
J Funct Biomater ; 14(4)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37103288

RESUMO

Green ZnO-decorated acid-activated bentonite-mediated curcumin extract (ZnO@CU/BE) was prepared as a multifunctional antioxidant and antidiabetic agent based on the extract of curcumin, which was used as a reducing and capping reagent. ZnO@CU/BE showed notably enhanced antioxidant properties against nitric oxide (88.6 ± 1.58%), 1,1-diphenyl-2-picrylhydrazil (90.2 ± 1.76%), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (87.3 ± 1.61%), and superoxide (39.5 ± 1.12%) radicals. These percentages are higher than the reported values of ascorbic acid as a standard and the integrated components of the structure (CU, BE/CU, and ZnO). This signifies the impact of the bentonite substrate on enhancing the solubility, stability, dispersion, and release rate of the intercalated curcumin-based phytochemicals, in addition to enhancing the exposure interface of ZnO nanoparticles. Therefore, effective antidiabetic properties were observed, with significant inhibition effects on porcine pancreatic α-amylase (76.8 ± 1.87%), murine pancreatic α-amylase (56.5 ± 1.67%), pancreatic α-glucosidase (96.5 ± 1.07%), murine intestinal α-glucosidase (92.5 ± 1.10%), and amyloglucosidase (93.7 ± 1.55%) enzymes. These values are higher than those determined using commercial miglitol and are close to the values measured using acarbose. Hence, the structure can be applied as an antioxidant and antidiabetic agent.

18.
Molecules ; 28(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36838844

RESUMO

In this study, we speculate that the hydroxyl-containing benzo[b]thiophene analogs, 1-(3-hydroxybenzo[b]thiophen-2-yl) ethanone (BP) and 1-(3-hydroxybenzo[b]thiophen-2-yl) propan-1-one hydrate (EP), might possess antiproliferative activity against cancer cells. Hydroxyl-containing BP and EP show selectivity towards laryngeal cancer cells (HEp2), with IC50 values of 27.02 ± 1.23 and 35.26 ± 2.15 µM, respectively. The hydroxyl group present in the third position is responsible for the anticancer activity and is completely abrogated when the hydroxyl group is masked. BP and EP enhance the antioxidant enzyme activity and reduce the ROS production, which are correlated with the antiproliferative effect in HEp-2 cells. An increase in the BAX/BCL-2 ratio occurs during the BP and EP treatment and activates the caspase cascade, resulting in apoptosis stimulation. It also arrests the cells in the Sub-G1 phase, indicating the induction of apoptosis. The molecular docking and simulation studies predicted a strong interaction between BP and the CYP1A2 protein, which could aid in combinational therapy by enhancing the bioavailability of the drugs. BP and EP possess an antioxidant property with low antiproliferative effects (~5.18 µg/mL and ~7.8 µg/mL) as a standalone drug, therefore, they can be combined with other drugs for effective chemotherapy that might trigger the effect of pro-oxidant drug on healthy cells.


Assuntos
Antineoplásicos , Carcinoma , Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/tratamento farmacológico , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , Apoptose , Fase G1 , Carcinoma/tratamento farmacológico , Proliferação de Células
19.
Nanomaterials (Basel) ; 14(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38202526

RESUMO

The development of efficient energy storage systems is critical in the transition towards sustainable energy solutions. In this context, the present work investigates the viability of using orange juice, as a promising and sustainable precursor, for the synthesis of activated carbon electrodes for supercapacitor technologies. Through the carbonization-activation process and controlling the preparation parameters (KOH ratio and activation time), we have tailored the specific surface area (SSA) and pore size distribution (PSD) of the resulting carbon materials-crucial parameters that support supercapacitive performance. Several spectroscopic, morphological, and electrochemical techniques are used to characterize the obtained carbon materials. In particular, our optimization efforts revealed that a 5:1 KOH ratio with an activation time up to 120 min produced the highest SSA of about 2203 m2/g. Employing these optimal conditions, we fabricated symmetric coin cell supercapacitors using Na2SO4 as the electrolyte, which exhibited interesting specific capacitance (~56 F/g). Durability testing over 5000 cycles sustained the durability of the as-made activated carbon electrodes, suggesting an excellent retention of specific capacitance. This study not only advances the field of energy storage by introducing a renewable material for electrode fabrication but also contributes to the broader goal of waste reduction through the repurposing of food byproducts.

20.
J Funct Biomater ; 13(4)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36412842

RESUMO

Background: We had previously synthetized a macromolecular prodrug consisting of oxidized Alginate and dopamine (AlgOx-Da) for a potential application in Parkinson disease (PD). Methods: In the present work, we aimed at gaining an insight into the interactions occurring between AlgOx-Da and SH-SY5Y neuronal cell lines in view of further studies oriented towards PD treatment. With the scope of ascertaining changes in the external and internal structure of the cells, multiple methodologies were adopted. Firstly, fluorescently labeled AlgOx-Da conjugate was synthetized in the presence of fluorescein 5(6)-isothiocyanate (FITC), providing FITC-AlgOx-Da, which did not alter SH-SY5Y cell viability according to the sulforhodamine B test. Furthermore, the uptake of FITC-AlgOx-Da by the SH-SY5Y cells was studied using scanning near-field optical microscopy and assessments of cell morphology over time were carried out using atomic force microscopy. Results: Notably, the AFM methodology confirmed that no relevant damage occurred to the neuronal cells. Regarding the effects of DA on the intracellular reactive oxygen species (ROS) production, AlgOx-Da reduced them in comparison to free DA, while AlgOx did almost not influence ROS production. Conclusions: these findings seem promising for designing in vivo studies aiming at administering Oxidized Alginate Dopamine Conjugate for PD treatment.

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