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1.
Chemphyschem ; 25(6): e202400184, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488206

RESUMO

The front cover artwork is provided by Dr habil. Izabella Jastrzebska's group from the University of Bialystok, Poland. The image shows a polymeric network with molecular rotors (MR) as crosslinks. The MR rotation is slowed or inhibited when a molecule of stored gas is placed inside the polymer material. Read the full text of the Research Article at 10.1002/cphc.202300793.

2.
Chemphyschem ; 25(6): e202300793, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38259120

RESUMO

In this paper, we report a new generation of polymeric networks as potential functional material based on changes in molecular dynamics in the solid state. The material is obtained by free radical polymerization of a diacrylate derivative bearing a steroid (stator) and a 1,4-diethynyl-phenylene-d4 fragment (rotator). Polymer research using the PALS technique complements the knowledge about nanostructural changes occurring in the system in the temperature range -115 °C - +190 °C. It indicates the presence of two types of free nanovolumes in the system and the occurrence of phase transitions. The polymer is characterized using 1 H NMR, 2 H Solid Echo NMR, ATR-FTIR and Raman spectroscopies, thermal analysis, and porosimetry. It is proved that the applied procedure leads to the formation of a novel porous organic material containing multiple molecular rotors.

3.
Polymers (Basel) ; 15(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38232016

RESUMO

Tissue accidents provide numerous pathways for pathogens to invade and flourish, causing additional harm to the host tissue while impeding its natural healing and regeneration. Essential oils (EOs) exhibit rapid and effective antimicrobial properties without promoting bacterial resistance. Clove oils (CEO) demonstrate robust antimicrobial activity against different pathogens. Chitosan (CS) is a natural, partially deacetylated polyamine widely recognized for its vast antimicrobial capacity. In this study, we present the synthesis of four membrane formulations utilizing CS, polyvinyl alcohol (PVA), and glycerol (Gly) incorporated with CEO and nanobioglass (n-BGs) for applications in subdermal tissue regeneration. Our analysis of the membranes' thermal stability and chemical composition provided strong evidence for successfully blending polymers with the entrapment of the essential oil. The incorporation of the CEO in the composite was evidenced by the increase in the intensity of the band of C-O-C in the FTIR; furthermore, the increase in diffraction peaks, as well as the broadening, provide evidence that the introduction of CEO perturbed the crystal structure. The morphological examination conducted using scanning electron microscopy (SEM) revealed that the incorporation of CEO resulted in smooth surfaces, in contrast to the porous morphologies observed with the n-BGs. A histological examination of the implanted membranes demonstrated their biocompatibility and biodegradability, particularly after a 60-day implantation period. The degradation process of more extensive membranes involved connective tissue composed of type III collagen fibers, blood vessels, and inflammatory cells, which supported the reabsorption of the composite membranes, evidencing the material's biocompatibility.

4.
Polymers (Basel) ; 14(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36145994

RESUMO

The use of biopolymers for tissue engineering has recently gained attention due to the need for safer and highly compatible materials. Starch is one of the most used biopolymers for membrane preparation. However, incorporating other polymers into starch membranes introduces improvements, such as better thermal and mechanical resistance and increased water affinity, as we reported in our previous work. There are few reports in the literature on the biocompatibility of starch/chicken gelatin composites. We assessed the in vivo biocompatibility of the five composites (T1-T5) cassava starch/gelatin membranes with subdermal implantations in biomodels at 30, 60, and 90 days. The FT-IR spectroscopy analysis demonstrated the main functional groups for starch and chicken gelatin. At the same time, the thermal study exhibited an increase in thermal resistance for T3 and T4, with a remaining mass (~15 wt.%) at 800 °C. The microstructure analysis for the T2-T4 demonstrated evident roughness changes with porosity presence due to starch and gelatin mixture. The decrease in the starch content in the composites also decreased the gelatinization heats for T3 and T4 (195.67, 196.40 J/g, respectively). Finally, the implantation results demonstrated that the formulations exhibited differences in the degradation and resorption capacities according to the starch content, which is easily degraded by amylases. However, the histological results showed that the samples demonstrated almost complete reabsorption without a severe immune response, indicating a high in vivo biocompatibility. These results show that the cassava starch/chicken gelatin composites are promising membrane materials for tissue engineering applications.

5.
Molecules ; 26(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34500714

RESUMO

Banana is a fruit grown mainly in tropical countries of the world. After harvest, almost 60% of banana biomass is left as waste. Worldwide, about 114.08 million metric tons of banana waste-loss are produced, leading to environmental problems such as the excessive emission of greenhouse gases. These wastes contain a high content of paramount industrial importance, such as cellulose, hemicellulose and natural fibers that various processes can modify, such as bacterial fermentation and anaerobic degradation, to obtain bioplastics, organic fertilizers and biofuels such as ethanol, biogas, hydrogen and biodiesel. In addition, they can be used in wastewater treatment methods by producing low-cost biofilters and obtaining activated carbon from rachis and banana peel. Furthermore, nanometric fibers commonly used in nanotechnology applications and silver nanoparticles useful in therapeutic cancer treatments, can be produced from banana pseudostems. The review aims to demonstrate the contribution of the recovery of banana production waste-loss towards a circular economy that would boost the economy of Latin America and many other countries of emerging economies.


Assuntos
Nanopartículas Metálicas/química , Musa/metabolismo , Prata/química , Biocombustíveis , Nanotecnologia/métodos
6.
Molecules ; 26(2)2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33478152

RESUMO

The food sector includes several large industries such as canned food, pasta, flour, frozen products, and beverages. Those industries transform agricultural raw materials into added-value products. The fruit and vegetable industry is the largest and fastest-growing segment of the world agricultural production market, which commercialize various products such as juices, jams, and dehydrated products, followed by the cereal industry products such as chocolate, beer, and vegetable oils are produced. Similarly, the root and tuber industry produces flours and starches essential for the daily diet due to their high carbohydrate content. However, the processing of these foods generates a large amount of waste several times improperly disposed of in landfills. Due to the increase in the world's population, the indiscriminate use of natural resources generates waste and food supply limitations due to the scarcity of resources, increasing hunger worldwide. The circular economy offers various tools for raising awareness for the recovery of waste, one of the best alternatives to mitigate the excessive consumption of raw materials and reduce waste. The loss and waste of food as a raw material offers bioactive compounds, enzymes, and nutrients that add value to the food cosmetic and pharmaceutical industries. This paper systematically reviewed literature with different food loss and waste by-products as animal feed, cosmetic, and pharmaceutical products that strongly contribute to the paradigm shift to a circular economy. Additionally, this review compiles studies related to the integral recovery of by-products from the processing of fruits, vegetables, tubers, cereals, and legumes from the food industry, with the potential in SARS-CoV-2 disease and bacterial diseases treatment.


Assuntos
Agricultura/métodos , Indústria Farmacêutica , Indústria Alimentícia , Resíduos/economia , Agricultura/economia , Cosméticos/economia , Grão Comestível , Indústria de Processamento de Alimentos/economia , Indústria de Processamento de Alimentos/métodos , Frutas , Raízes de Plantas , Tubérculos , Verduras
7.
Data Brief ; 30: 105579, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32382602

RESUMO

The article show the date associated with the work previously reported "Design, theoretical and correlation of the electronic and optical properties of diethynylphenylthiophene as photovoltaic materials", https://doi.org/10.1016/j.molstruc.2019.127093[1]. The authors reported graphics and tables building from of p-PDT, m-PDT, o-PDT, p-ZnPDT, m -ZnPDT and o-ZnPDT calculations as raw date, with the aim of to show electronic and optical properties, which can be analyzed by the reader. In this context, there exists an important number of renewable energies that are substituting the oil and the charcoal be used in the energetic supply. One of these alternatives is the use of solar cells, which can be use in diverse areas like telecommunications, remote systems of monitoring, lighting systems, water treatment systems, and products of consumption. The employment of the organic photovoltaic technology and photosensitized organic materials are based on the use of molecular organic materials for coverings for ceiling and windows of a house that allow the storage of energy. The OPVs and DSSC present π conjugated systems, giving them a high electronic relocated density, which allows catching the radiations with an energy range of wavelengths between 400 and 800 nm. The systems are derived of diethynylphenylthiophene (LMWOM) coupled to phenyldiamine (PD) as spacer, forming hyper conjugated macrocycles (p-PDT, m-PDT, o-PDT, p-ZnPDT, m -ZnPDT and o-ZnPDT). On the other hand, it is reported process electronic relationship with material sensitized and the bibliographic support of the publication topic.

8.
Molecules ; 25(10)2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32423061

RESUMO

Scaffold development for cell regeneration has increased in recent years due to the high demand for more efficient and biocompatible materials. Nanomaterials have become a critical alternative for mechanical, thermal, and antimicrobial property reinforcement in several biopolymers. In this work, four different chitosan (CS) bead formulations crosslinked with glutaraldehyde (GLA), including titanium dioxide nanoparticles (TiO2), and graphene oxide (GO) nanosheets, were prepared with potential biomedical applications in mind. The characterization of by FTIR spectroscopy, X-ray photoelectron spectroscopy (XRD), thermogravimetric analysis (TGA), energy-dispersive spectroscopy (EDS) and scanning electron microscopy (SEM), demonstrated an efficient preparation of nanocomposites, with nanoparticles well-dispersed in the polymer matrix. In vivo, subdermal implantation of the beads in Wistar rat's tissue for 90 days showed a proper and complete healing process without any allergenic response to any of the formulations. Masson's trichrome staining of the histological implanted tissues demonstrated the presence of a group of macrophage/histiocyte compatible cells, which indicates a high degree of biocompatibility of the beads. The materials were very stable under body conditions as the morphometry studies showed, but with low resorption percentages. These high stability beads could be used as biocompatible, resistant materials for long-term applications. The results presented in this study show the enormous potential of these chitosan nanocomposites in cell regeneration and biomedical applications.


Assuntos
Quitosana/química , Grafite/química , Nanocompostos/química , Nanopartículas/química , Alicerces Teciduais , Titânio/química , Animais , Materiais Biocompatíveis , Sobrevivência Celular/efeitos dos fármacos , Quitosana/farmacologia , Grafite/farmacologia , Histiócitos/citologia , Histiócitos/efeitos dos fármacos , Histiócitos/fisiologia , Masculino , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Ratos , Ratos Wistar , Pele/citologia , Pele/efeitos dos fármacos , Engenharia Tecidual/métodos , Titânio/farmacologia
9.
Biomolecules ; 9(9)2019 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500281

RESUMO

Red Tilapia is one of the most consumed but perishable fish in the world. As a result, it requires preservation methods for safe consumption without affecting its organoleptic characteristics. Chitosan encapsulating essential oils have shown to be an excellent food conservation method. For that reason, we carried out the study of the protective effect on red Tilapia fillets with chitosan beads (CB) incorporated with Thymus capitatus (TCEO) essential oil at 500, 1000, and 2000 mg/L to assess the conservation of the fillets. The TCEO composition was characterized by gas chromatography-mass spectrometry (CG-MS). For the other side, CB was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), thermogravimetric analysis (TGA), and Scanning electron microscopy (SEM). The protective effect of the beads was tested against the Gram-positive and Gram-negative bacteria growth for four weeks. The results showed an inhibition effect in Gram-positive bacteria at higher TCEO concentration (1000 and 2000 mg/L). Besides that, the pH, total volatile basic nitrogen (T-BNV-N), color, and fillet texture were evaluated as quality attributes. The results suggested that the incorporation of the CB-TCEO allowed a higher contact of the active compounds with the food surface, which reflected more excellent stability. The quality attributes of the fillets were preserved for 26 days, suggesting its uses for the treatment for perishable food.


Assuntos
Antibacterianos/farmacologia , Quitosana/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Óleos Voláteis/farmacologia , Thymus (Planta)/química , Animais , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacologia , Quitosana/química , Conservação de Alimentos , Armazenamento de Alimentos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Tilápia
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