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1.
JMIR Res Protoc ; 13: e53703, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819917

RESUMO

BACKGROUND: A dietary supplement containing Pelargonium sidoides extract, propolis, zinc, and honey has been recently developed and proven to be an effective adjuvant in clinical practice for seasonal diseases and the treatment of respiratory tract disorders. OBJECTIVE: This trial aims to verify the efficacy of the tested dietary supplement in a pediatric population with acute tonsillopharyngitis/rhinopharyngitis (ATR). METHODS: The trial includes children aged between 3 and 10 years with ATR ≤48 h, a negative rapid test for beta-hemolytic streptococcus or culture identification of nasal and/or pharyngeal exudates, and SARS-CoV-2 infection. The dietary supplement tested is an oral solution already on the market based on Pelagon P-70 (equivalent to Pelargonium sidoides d.e. 133.3 mg/100 ml), propolis, zinc, and honey. The product is administered at 5 ml 3 times a day for 6 days for children younger than 6 years and 10 ml 3 times a day for 6 days for children older than 6 years. The study design is open label, randomized, and controlled, with the tested dietary supplement plus standard of care (SoC) versus SoC alone. Patients are enrolled from 3 sites in Romania. The change in Tonsillitis Severity Score and number of treatment failures (using ibuprofen or high-dose paracetamol as rescue medication) are the primary end points. Based on the Tonsillitis Severity Score and the 2-sample comparison of the means formula with a 5% significance level, 80% power, and a minimally clinically important difference of 2 (SD 3.85) points, 120 patients are required. To account for potential screening failures and dropouts, we need to screen a population of approximately 150 children. RESULTS: Patient enrollment began on June 3, 2021 (first patient's first visit), and ended on August 12, 2021 (last patient's last visit). The data collection period was from June 3, 2021, to September 16, 2021. The study was funded in February 2023. Data analysis is currently ongoing (April 2024). We expect the results to be published in a peer-reviewed clinical journal in the third quarter of 2024 and presented at scientific meetings in the last quarter of 2024. CONCLUSIONS: The data from this trial may help identify new adjuvant treatments for children with ATR when streptococcal infection is excluded by a negative rapid test, thereby avoiding unnecessary antibiotic administration. TRIAL REGISTRATION: ClinicalTrials.gov NCT04899401 https://clinicaltrials.gov/study/NCT04899401. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53703.


Assuntos
Suplementos Nutricionais , Mel , Faringite , Tonsilite , Humanos , Criança , Pré-Escolar , Faringite/tratamento farmacológico , Tonsilite/tratamento farmacológico , Tonsilite/microbiologia , Masculino , Feminino , Padrão de Cuidado , Doença Aguda , COVID-19 , Própole/uso terapêutico , Própole/administração & dosagem , Zinco/uso terapêutico , Zinco/administração & dosagem , Extratos Vegetais/uso terapêutico , Extratos Vegetais/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Molecules ; 29(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675662

RESUMO

Membrane materials with osmium nanoparticles have been recently reported for bulk membranes and supported composite membrane systems. In the present paper, a catalytic material based on osmium dispersed in n-decanol (nD) or n-dodecanol (nDD) is presented, which also works as an emulsion membrane. The hydrogenation of p-nitrophenol (PNP) is carried out in a reaction and separation column in which an emulsion in the acid-receiving phase is dispersed in an osmium nanodispersion in n-alcohols. The variables of the PNP conversion process and p-aminophenol (PAP) transport are as follows: the nature of the membrane alcohol, the flow regime, the pH difference between the source and receiving phases and the number of operating cycles. The conversion results are in all cases better for nD than nDD. The counter-current flow regime is superior to the co-current flow. Increasing the pH difference between the source and receiving phases amplifies the process. The number of operating cycles is limited to five, after which the regeneration of the membrane dispersion is required. The apparent catalytic rate constant (kapp) of the new catalytic material based on the emulsion membrane with the nanodispersion of osmium nanoparticles (0.1 × 10-3 s-1 for n-dodecanol and 0.9 × 10-3 s-1 for n-decanol) is lower by an order of magnitude compared to those based on adsorption on catalysts from the platinum metal group. The advantage of the tested membrane catalytic material is that it extracts p-aminophenol in the acid-receiving phase.

3.
Antioxidants (Basel) ; 13(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38397847

RESUMO

Polyphenolic extracts from wild bilberries (Vaccinium myrtillus L.) have shown antioxidant and anti-inflammatory effects, but they are prone to degradation when exposed to environmental factors, limiting their use in biomedical applications. To overcome this issue, this study proposed the embedding of wild bilberry fruit ethanolic extracts in pristine mesoporous silica functionalized with organic groups (mercaptopropyl and propionic acid), as well as coated with fucoidan, a biopolymer. Herein, we report a stability study of free and incorporated extracts in mesoporous silica-type supports in high-humidity atmospheres at 40 °C up to 28 days, using HPLC analysis, thermal analysis, and radical scavenging activity determination. Better chemical and thermal stability over time was observed when the extracts were incorporated in mesoporous silica-type supports. After 12 months of storage, higher values of antioxidant activity were determined for the extract embedded in the supports, silica modified with mercaptopropyl groups (MCM-SH), and fucoidan-coated silica (MCM-SH-Fuc) than that of the free extract due to a synergistic activity between the support and extract. All encapsulated extracts demonstrated remarkable effects in reducing NO production in LPS-stimulated RAW 264.7 cells. The treatment with extract embedded in MCM-SH-Fuc in a dose of 10 µg/mL surpassed the effect of free extract in the same concentration. For the extract encapsulated in an MCM-SH support, a lower IC50 value (0.69 µg/mL) towards COX-2 was obtained, comparable with that of Indomethacin (0.6 µg/mL). Also, this sample showed a higher selectivity index (2.71) for COX-2 than the reference anti-inflammatory drug (0.98). The developed formulations with antioxidant and anti-inflammatory properties could be further used in nutraceuticals.

4.
Biosensors (Basel) ; 13(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37622867

RESUMO

A sensing platform based on nanocomposite materials composed of gold metal nanoparticles (AuNPs) and conducting polymer (CP) matrix has been developed for serotonin and epinephrine detection. The CP-AuNPs nanocomposite materials have been synthesized onto glassy carbon electrodes (GCE) by using novel electrochemical procedures based on sinusoidal currents (SC). The SC procedures ensured good control of the metal nanoparticles distribution, increased electrochemical surface area, and enhanced analytical performance. The proposed sensing platform displayed good analytical performance toward serotonin and epinephrine detection. A wide linear analytical response toward epinephrine in the range from 10 to 640 µM and a low detection limit of 1.4 µM epinephrine has been obtained. The sensing platform has also displayed a linear response toward serotonin in the range from 10 to 320 µM, with a detection limit of 5.7 µM serotonin. The sensing platform has been successfully applied in the analysis of epinephrine and serotonin in real samples of tap water and urine with good accuracy.


Assuntos
Líquidos Corporais , Nanopartículas Metálicas , Ouro , Serotonina , Epinefrina , Polímeros
5.
Molecules ; 28(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37570765

RESUMO

Polyphenolic extracts from natural sources have received great interest due to their beneficial properties for human health. A method to reduce their variability is to use the design of experiments which allows a limited number of experiments to be performed while exploring the experimental space. Firstly, a 23-full factorial model was used to investigate the polyphenols extraction from wild bilberry leaves. Spectrophotometric data (the content of polyphenols, flavonoids, chlorophyll and radical scavenger activity) and extraction yield were used as responses, and six statistical models were determined depending on the two numerical factors (temperature and alcohol % of ethanol-water mixture) being significant (p < 0.05) in all cases. Numerical optimisation performed by Design Expert 13 software correlates well with the chemical profile determined by high-performance liquid chromatography and the amount of the polyphenol. Afterwards, under the optimised conditions, an extract was prepared in three extraction steps for which composition, chemical stability and antimicrobial properties were evaluated. The antimicrobial potential of the extract was compared with that of the standard compounds (rutin and chlorogenic acid), and the results supported a synergistic effect of the extract components.


Assuntos
Anti-Infecciosos , Vaccinium myrtillus , Humanos , Polifenóis/química , Vaccinium myrtillus/química , Antioxidantes/química , Flavonoides/química , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/análise , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Folhas de Planta/química
6.
Pharmaceutics ; 15(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36839635

RESUMO

Lesions can affect skin functions and cause a simple issue, such as dehydration, or more challenging complications, such as bacterial infections. The purpose of this study was to design composites for topical application that can prevent and/or assist in bacterial infections and support cell regeneration using natural components. A polyphenolic extract obtained from Salvia officinalis was embedded in functionalized mesoporous silica nanoparticles for better stability, followed by their distribution into a collagen porous scaffold. The resulting polyphenols-loaded MSN exhibited enhanced antibacterial activity and good cytocompatibility. Improved thermal stability of the collagen porous scaffold was obtained due to the presence of the functionalized MSN. For the first time, collagen-polyphenols-loaded silica composites were reported in the literature as potential wound dressings. The newly developed composites showed excellent sterility.

7.
Materials (Basel) ; 15(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36234345

RESUMO

Natural compounds are an important source of beneficial components that could be used in cancer therapy along with well-known cytostatic agents to enhance the therapeutic effect while targeting tumoral tissues. Therefore, nanoplatforms containing mesoporous silica and a natural polysaccharide, ulvan, extracted from Ulva Lactuca seaweed, were developed for irinotecan. Either mesoporous silica-ulvan nanoplatforms or irinotecan-loaded materials were structurally and morphologically characterized. In vitro drug release experiments in phosphate buffer solution with a pH of 7.6 emphasized the complete recovery of irinotecan in 8 h. Slower kinetics were obtained for the nanoplatforms with a higher amount of natural polysaccharide. Ulvan extract proved to be biocompatible up to 2 mg/mL on fibroblasts L929 cell line. The irinotecan-loaded nanoplatforms exhibited better anticancer activity than that of the drug alone on human colorectal adenocarcinoma cells (HT-29), reducing their viability to 60% after 24 h. Moreover, the cell cycle analysis proved that the irinotecan loading onto developed nanoplatforms caused an increase in the cell number trapped at G0/G1 phase and influenced the development of the tumoral cells.

8.
Membranes (Basel) ; 12(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36295782

RESUMO

Liquid membranes based on nanoparticles follow a continuous development, both from obtaining methods and characterization of techniques points of view. Lately, osmium nanoparticles have been deposited either on flat membranes, with the aim of initiating some reaction processes, or on hollow fiber membranes, with the aim of increasing the contact surface with the phases of the membrane system. This paper presents the obtainment and characterization of a liquid membrane based on osmium nanoparticles (Os-NP) dispersed in ndecanol (nDol) for the realization of a membrane system with a large contact surface between the phases, but without using a liquid membrane support. The dispersion of osmium nanoparticles in n-decanol is carried out by the method of reducing osmium tetroxide with 1-undecenoic acid (UDA). The resulting membrane was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive spectroscopy analysis (EDAX), thermoanalysis (TG, DSC), Fourier transform infra-red (FTIR) spectroscopy and dynamic light scattering (DLS). In order to increase the mass transfer surface, a design for the membrane system was realized with the dispersion of the membrane through the receiving phase and the dispersion of the source phase through the membrane (DBLM-dispersion bulk liquid membrane). The process performance was tested for the reduction of p-nitrophenol (pNP) from the source phase, using sodium tetra-borohydride (NaBH4), to p-aminophenol (pAP), which was transported and collected in the receiving phase. The obtained results show that membranes based on the dispersion of osmium nanoparticles in n-decanol can be used with an efficiency of over 90% for the reduction of p-nitrophenol and the separation of p-aminophenol.

9.
Materials (Basel) ; 15(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36079388

RESUMO

Materials used in the marine industry are exposed to extreme conditions, so it is necessary to meet remarkable characteristics, such as mechanical resistance, low density, and good corrosion resistance. The challenging environment requires continuous performance improvements, so this work is focused on developing new materials with superior properties, using the electrochemical deposition technique, which are convenient for marine engineering. High-entropy alloys have been attracting tremendous interest in many applications, due to their simple crystal structures and advantageous physical-chemical properties, such as high strength, anti-corrosion, erosion, and electro-magnetic capabilities. To identify the most appropriate compositions, MatCalc software was used to predict the structure and characteristics of the required materials, and thermodynamic and kinetic criteria calculations were performed. The modelling processes generated a series of optimal compositions in the AlCrCuFeNi alloy system, that are suitable to be used in anticorrosive and tribological applications. The composition and morphology of the obtained high entropy alloy thin films revealed a uniform structure, with a small grain profile. The corrosion resistance was investigated in artificial seawater to observe the behavior of the newly developed materials in demanding conditions, and the results showed improved results compared to the copper foil substrate.

10.
Nanoscale ; 14(35): 12744-12756, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36000453

RESUMO

Using nanoparticles as carriers for drug delivery systems has become a widely applied strategy in therapeutics and diagnostics. However, the pattern of their intracellular distribution is yet to be clarified. Here we present an in vitro study on the incorporation of mesoporous silica nanoparticles conjugated with folate and loaded with a cytotoxic drug, Irinotecan. The nanoparticles count and distribution within the cell frame were evaluated by means of enhanced dark field microscopy combined with hyperspectral imagery and 3D reconstructions from double-labeled fluorescent samples. An original post-processing procedure was developed to emphasize the nanoparticles' localization in 3D reconstruction of cellular compartments. By these means, it has been shown that the conjugation of mesoporous silica nanoparticles with folate increases the efficiency of nanoparticles entering the cell and their preferential localization in the close vicinity of the nucleus. As revealed by metabolic viability assays, the nanoparticles functionalized with folate enhance the cytotoxic efficiency of Irinotecan.


Assuntos
Antineoplásicos , Nanopartículas , Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Ácido Fólico , Células HeLa , Humanos , Irinotecano , Microscopia , Porosidade , Dióxido de Silício
11.
Pharmaceutics ; 14(1)2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35057098

RESUMO

Resveratrol, a naturally occurring polyphenol, has attracted significant attention due to its antioxidant, cardioprotective and anticancer potential. However, its low aqueous solubility limits resveratrol bioavailability and use. In this work, different mesoporous silica matrices were used to encapsulate the polyphenol and to increase its dissolution rate. Pristine MCM-41, MCM-48, SBA-15, SBA-16, FDU-12 and MCF silica were obtained. The influence of SBA-15 functionalized with aminopropyl, isocyanate, phenyl, mercaptopropyl, and propionic acid moieties on resveratrol loading and release profiles was also assessed. The cytotoxic effects were evaluated for mesoporous carriers and resveratrol-loaded samples against human lung cancer (A549), breast cancer (MDA-MB-231) and human skin fibroblast (HSF) cell lines. The effect on apoptosis and cell cycle were assayed for selected resveratrol-loaded carriers. The polyphenol molecules are encapsulated only inside the mesopores, mostly in amorphous state. All materials containing either pristine or functionalized silica carriers increased polyphenol dissolution rate. The influence of the physico-chemical properties of the mesoporous carriers and resveratrol-loaded supports on the kinetic parameters was identified. Resv@SBA-15-SH and Resv@SBA-15-NCO samples exhibited the highest anticancer effect against A549 cells (IC50 values were 26.06 and 36.5 µg/mL, respectively) and against MDA-MB-231 (IC50 values were 35.56 and 19.30 µg/mL, respectively), which highlights their potential use against cancer.

12.
Materials (Basel) ; 14(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34771983

RESUMO

To improve phytochemical stability, polyphenolic extracts prepared from Salvia officinalis L., which is a valuable source of phytocompounds with health benefits, were embedded into mesopores of silica, titania, or titania-ceria materials. Ethanolic and hydroalcoholic extracts were prepared by conventional, microwave- or ultrasound-assisted extraction. The influence of the extraction conditions on chemical profile, radical scavenger activity (RSA), and antimicrobial potential of the extracts was assessed. The extracts were characterized by spectrophotometric determination of total polyphenols, flavonoids, chlorophyll pigment contents, as well as RSA. A reverse phase HPLC- PDA analysis was performed for the identification and quantification of extract polyphenols. The extract-loaded materials exhibited an enhanced RSA compared to the free extract after several months of storage, resulting in better polyphenol stability over time following embedding into a mesoporous matrix. Selected extracts free and embedded into mesoporous support were tested against Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, and Staphylococcus aureus ATCC 25923; the best antimicrobial activity was obtained for S. aureus. A slight improvement in antimicrobial activity was observed for the ethanolic extract prepared by ultrasound-assisted extraction following embedding into the TiO2 matrix compared to MCM-41 silica due to the support contribution.

13.
Chem Biodivers ; 18(8): e2100293, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34156756

RESUMO

Acid-soluble, undenatured, type I collagen (BSC) isolated, for the first time, from gilthead bream skin and the novel fabricated 3D porous wound dressing were analyzed for physicochemical and biological properties, in order to offer a safe alternative to commercial bovine collagen (BC) products. SDS-polyacrylamide analysis confirmed the purity of BSC preparation. The hydroxyproline content and temperature of denaturation of BSC were lower than those of BC, in accordance with the structural data recorded by FT-IR spectroscopy. However, certain concentrations of BSC stimulated the cell metabolism of L929 fibroblasts in a higher proportion than BC. The 3D wound dressing presented high porosity and low surface hydrophobicity that could help cell attachment and growth. The rapid biodegradation of BSC wound dressing could explain the improved in vitro cell migration and wound closure rate. In conclusion, the skin of gilthead bream from the Black Sea coast represented a valuable source for the biomedical industry, providing biocompatible, biodegradable collagen and 3D porous wound dressing, as novel material with enhanced wound healing activity.


Assuntos
Bandagens , Colágeno Tipo I/farmacologia , Dourada/metabolismo , Pele/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Mar Negro , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/isolamento & purificação , Colágeno Tipo I/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Hidroxiprolina/química , Hidroxiprolina/metabolismo , Camundongos , Peso Molecular , Porosidade , Desnaturação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura de Transição
14.
Biomed Mater ; 16(3)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33571971

RESUMO

Severe skin injuries, including burns, represent a real concern for the global health-care system and therefore, there is an increased interest in developing wound dressings, in order to stimulate and enhance skin tissue repair. The aim of this study was to design novel hybrid materials, biomimetic to skin extracellular matrix and enriched with silver nanoparticles (nAg), in order to provide both dermal tissue regeneration and antimicrobial activity. Two material variants (variant A and variant B) consisting of type I collagen (COL), chondroitin sulfate (CS) and k-elastin peptides (EL) enriched with positively-charged nAg, were conditioned as membranes. UV exposure ensured both sterilisation and cross-linking of the materials. Physico-chemical characterization of the hybrid biomaterials showed values of density and swelling degree higher than those of COL membrane, while the process ofin vitrodegradation followed a similar pattern. Infrared spectroscopy and x-ray diffraction indicated alterations of the characteristic structural features and crystallinity of COL after blending with CS and EL and nAg embedding. Scanning electron microscopy observations revealed different surface morphologies of the hybrid membranes, according to their composition.In vitrostudies on L929 fibroblasts and HaCaT keratinocytes showed that both hybrid membranes exhibited good cytocompatibility and promoted higher cell proliferation compared to COL sample, as evaluated by MTT and Live/Dead assays. The presence of actin filaments highlighted by fluorescent labelling confirmed the fibroblast and keratinocyte adhesion onto the surface of hybrid membranes. Most importantly, both materials showed an increased wound healing ability in anin vitroscratch assay model, stimulating cell migration at 24 h post-seeding. In addition, good antimicrobial activity was recorded, especially against Gram-positive bacterial strain. Altogether, our findings recommend COL-CS-EL-nAg hybrid membranes as good candidates for wound healing acceleration and bioengineering of skin tissue.


Assuntos
Nanopartículas Metálicas , Prata , Biomimética , Colágeno/química , Matriz Extracelular , Fibroblastos , Nanopartículas Metálicas/química , Prata/química , Cicatrização
15.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466451

RESUMO

Phase change materials (PCMs) can store thermal energy as latent heat through phase transitions. PCMs using the solid-liquid phase transition offer high 100-300 J g-1 enthalpy at constant temperature. However, pure compounds suffer from leakage, incongruent melting and crystallization, phase separation, and supercooling, which limit their heat storage capacity and reliability during multiple heating-cooling cycles. An appropriate approach to mitigating these drawbacks is the construction of composites as shape-stabilized phase change materials which retain their macroscopic solid shape even at temperatures above the melting point of the active heat storage compound. Shape-stabilized materials can be obtained by PCMs impregnation into porous matrices. Porous silica nanomaterials are promising matrices due to their high porosity and adsorption capacity, chemical and thermal stability and possibility of changing their structure through chemical synthesis. This review offers a first in-depth look at the various methods for obtaining composite PCMs using porous silica nanomaterials, their properties, and applications. The synthesis and properties of porous silica composites are presented based on the main classes of compounds which can act as heat storage materials (paraffins, fatty acids, polymers, small organic molecules, hydrated salts, molten salts and metals). The physico-chemical phenomena arising from the nanoconfinement of phase change materials into the silica pores are discussed from both theoretical and practical standpoints. The lessons learned so far in designing efficient composite PCMs using porous silica matrices are presented, as well as the future perspectives on improving the heat storage materials.


Assuntos
Nanoestruturas/química , Transição de Fase , Dióxido de Silício/química , Temperatura , Condutividade Térmica , Termodinâmica
16.
Antioxidants (Basel) ; 9(8)2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756379

RESUMO

The aim of this paper is to assess the properties of Mamaia (MM) grape pomace polyphenolic extract loaded onto pristine and functionalized MCM-41 mesoporous silica as potential ingredients for nutraceuticals or cosmetics. The chemical profile of hydroalcoholic polyphenolic extracts, prepared either by conventional extraction or microwave-assisted method, was analyzed by reverse-phase high-performance liquid chromatography with photodiode array detector (HPLC-PDA) analysis, while their radical scavenger activity (RSA) was evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) assays. The extract-loaded materials were characterized by Fourier transform infrared (FTIR) spectroscopy, N2 adsorption-desorption isotherms, thermogravimetric analysis, as well as RSA (DPPH and ABTS assays). The polyphenols release profiles from pristine and functionalized (with mercaptopropyl, propyl sulfonic acid, cyanoethyl and propionic acid moieties) MCM-41-type supports were determined in phosphate buffer solution (PBS) pH 5.7. For selected materials containing embedded phytochemicals, cellular viability, and oxidative stress level on immortalized mouse embryonic fibroblast cell line (NIH3T3) were evaluated. A more acidic functional groups linked on silica pore walls determined a higher amount of phytochemicals released in PBS. The extract-loaded materials showed a good cytocompatibility on tested concentrations. The embedded extract preserved better the RSA over time than the free extract. The polyphenols-loaded MCM-41-type silica materials, especially MM@MCM-COOH material, demonstrated a good in vitro antioxidant effect on NIH3T3 cells, being potential candidates for nutraceutical or cosmetic formulations.

17.
Nanomaterials (Basel) ; 10(5)2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344938

RESUMO

This study evidenced the nanoconfinement effect on polyphenolic extracts prepared from Salvia officinalis L. and Thymus serpyllum L. into the mesopores of silica and titania nanomaterials on their radical scavenging capacity and antimicrobial potential. The ethanolic and hydroalcoholic extracts obtained either by conventional or microwave-assisted extraction were characterized in terms of total polyphenols, total flavonoids, and chlorophyll content, as well as radical scavenging activity by consecrated spectrometric determinations. The phytochemical fingerprint of extracts was analyzed by high-performance liquid chromatography-photodiode array detector. Salvia officinalis extracts exhibited better radical scavenging capacity and antimicrobial potential than Thymus serpyllum extracts. The mesoporous MCM-41 silica and titania nanomaterials, prepared by the sol-gel method, were characterized by small- and wide-angle powder diffraction, FTIR spectroscopy, nitrogen adsorption-desorption isotherms, scanning electron microscopy and transmission electron microscopy, while the materials containing embedded extracts were analyzed through Fourier-transform infrared spectroscopy, N2 sorption measurements, and thermal analysis. All extracts free and embedded in mesoporous matrix exhibited high radical scavenger properties and good bactericidal activity against several reference strains. It was proved that by embedding the polyphenolic extracts into mesopores of silica or titania nanoparticles, the phytochemicals stability was enhanced as the materials containing extract exhibited higher radical scavenger activity after 3-6 months storage than that of the free extracts. Additionally, the extract-loaded material showed mild improved antimicrobial activity in comparison with the corresponding free extract.

18.
Nanomaterials (Basel) ; 10(3)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155937

RESUMO

A facile and cheap surfactant-assisted hydrothermal method was used to prepare mesoporous cobalt ferrite nanosystems with BET surface area up to 151 m2/g. These mesostructures with high BET surface areas and pore sizes are made from assemblies of nanoparticles (NPs) with average sizes between 7.8 and 9.6 nm depending on the initial pH conditions. The pH proved to be the key factor for controlling not only NP size, but also the phase purity and the porosity properties of the mesostructures. At pH values lower than 7, a parasite hematite phase begins to form. The sample obtained at pH = 7.3 has magnetization at saturation Ms = 38 emu/g at 300 K (54.3 emu/g at 10 K) and BET surface area SBET = 151 m2/g, whereas the one obtained at pH = 8.3 has Ms = 68 emu/g at 300 K (83.6 emu/g at 10 K) and SBET = 101 m2/g. The magnetic coercive field values at 10 K are high at up to 12,780 Oe, with a maximum coercive field reached for the sample obtained at pH = 8.3. Decreased magnetic performances are obtained at pH values higher than 9. The iron occupancies of the tetrahedral and octahedral sites belonging to the cobalt ferrite spinel structure were extracted through decomposition of the Mössbauer patterns in spectral components. The magnetic anisotropy constants of the investigated NPs were estimated from the temperature dependence of the hyperfine magnetic field. Taking into consideration the high values of BET surface area and the magnetic anisotropy constants as well as the significant magnetizations for saturation at ambient temperature, and the fact that all parameters can be adjusted through the initial pH conditions, these materials are very promising as recyclable anti-polluting agents, magnetically separable catalysts, and targeted drug delivery vehicles.

19.
Nanomaterials (Basel) ; 10(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881758

RESUMO

The paper deals with the preparation and characterisation of hydroalcoholic polyphenolic extract from Sambucus ebulus (SE) leaves that was further loaded into three-types of lipid vesicles: liposomes, transfersomes, and ethosomes, to improve its bioavailability and achieve an optimum pharmacological effect. For Sambucus ebulus L.-loaded lipid vesicles, the entrapment efficiency, particle size, polydispersity index and stability were determined. All prepared lipid vesicles showed a good entrapment efficiency, in the range of 75-85%, nanometric size, low polydispersity indexes, and good stability over three months at 4 °C. The in vitro polyphenols released from lipid vehicles demonstrated slower kinetics when compared to the free extract dissolution in phosphate buffer solution at pH 7.4. Either free SE extract or SE extract loaded into lipid vesicles demonstrated a cytoprotective effect, even at low concentration, 5 ug/mL, against hydrogen peroxide-induced toxicity on L-929 mouse fibroblasts' cell lines. However, the cytoprotective effect depended on the time of the cells pre-treatment with SE extract before exposure to a hydrogen peroxide solution of 50 mM concentration, requiring at least 12 h of pre-treatment with polyphenols with radical scavenging capacity.

20.
Mar Drugs ; 17(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627413

RESUMO

In this study, we aimed to obtain gelatin from the marine snail Rapana venosa using acidic and enzymatic extraction methods and to characterize these natural products for cosmetic and pharmaceutical applications. Marine gelatins presented protein values and hydroxyproline content similar to those of commercial mammalian gelatin, but with higher melting temperatures. Their electrophoretic profile and Fourier transform infrared (FTIR) spectra revealed protein and absorption bands situated in the amide region, specific for gelatin molecule. Scanning electron microscopy (SEM) analysis showed significant differences in the structure of the lyophilized samples, depending on the type of gelatin. In vitro studies performed on human keratinocytes showed no cytotoxic effect of acid-extracted gelatin at all tested concentrations and moderate cytotoxicity of enzymatic extracted gelatin at concentrations higher than 0.5 mg/mL. Also, both marine gelatins favored keratinocyte cell adhesion. No irritant potential was recorded as the level of IL-1α and IL-6 proinflammatory cytokines released by HaCaT cells cultivated in the presence of marine gelatins was significantly reduced. Together, these data suggest that marine snails are an alternative source of gelatins with potential use in pharmaceutical and skincare products.


Assuntos
Organismos Aquáticos/química , Produtos Biológicos/química , Gelatina/química , Caramujos/química , Animais , Produtos Biológicos/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Citocinas/metabolismo , Gelatina/farmacologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo
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