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1.
J Hazard Mater ; 470: 134190, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593659

RESUMO

Organophosphorus compounds (OPs), such as VX, pose a significant threat due to their neurotoxic and hazardous properties. Skin decontamination is essential to avoid irreversible effects. Fuller's earth (FE), a phyllosilicate conventionally employed in powder form, has demonstrated decontamination capacity against OPs. The aim of this study was to develop a formulation that forms a film on the skin, with a significant OP removal capacity (>95 %) coupled with sequestration capabilities, favorable drying time and mechanical properties to allow for easy application and removal, particularly in emergency context. Various formulations were prepared using different concentrations of polyvinyl alcohol (PVA), FE and surfactants. Their removal and sequestration capacity was tested using paraoxon-ethyl (POX), a chemical that simulates the behavior of VX. Formulations with removal capacity levels surpassing 95 % were mechanically characterized and cell viability assays were performed on Normal Human Dermal Fibroblast (NHDF). The four most promising formulations were used to assess decontamination efficacy on pig ear skin explants. These formulations showed decontamination levels ranging from 84.4 ± 4.7 % to 96.5 ± 1.3 %, which is equivalent to current decontamination methods. These results suggest that this technology could be a novel and effective tool for skin decontamination following exposure to OPs.


Assuntos
Descontaminação , Paraoxon , Pele , Descontaminação/métodos , Animais , Pele/efeitos dos fármacos , Humanos , Suínos , Paraoxon/toxicidade , Paraoxon/química , Compostos de Alumínio/química , Sobrevivência Celular/efeitos dos fármacos , Silicatos/química , Álcool de Polivinil/química , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Tensoativos/química , Fibroblastos/efeitos dos fármacos
2.
Nat Commun ; 15(1): 3435, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653959

RESUMO

Wound healing is an obvious clinical concern that can be hindered by inadequate angiogenesis, inflammation, and chronic hypoxia. While exosomes derived from adipose tissue-derived stem cells have shown promise in accelerating healing by carrying therapeutic growth factors and microRNAs, intracellular cargo delivery is compromised in hypoxic tissues due to activated hypoxia-induced endocytic recycling. To address this challenge, we have developed a strategy to coat oxygen nanobubbles with exosomes and incorporate them into a polyvinyl alcohol/gelatin hybrid hydrogel. This approach not only alleviates wound hypoxia but also offers an efficient means of delivering exosome-coated nanoparticles in hypoxic conditions. The self-healing properties of the hydrogel, along with its component, gelatin, aids in hemostasis, while its crosslinking bonds facilitate hydrogen peroxide decomposition, to ameliorate wound inflammation. Here, we show the potential of this multifunctional hydrogel for enhanced healing, promoting angiogenesis, facilitating exosome delivery, mitigating hypoxia, and inhibiting inflammation in a male rat full-thickness wound model.


Assuntos
Exossomos , Hidrogéis , Oxigênio , Cicatrização , Exossomos/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Hidrogéis/química , Masculino , Ratos , Oxigênio/metabolismo , Humanos , Ratos Sprague-Dawley , Nanopartículas/química , Álcool de Polivinil/química , Neovascularização Fisiológica/efeitos dos fármacos , Gelatina/química , Hipóxia/metabolismo , Inflamação/metabolismo
3.
J Mater Chem B ; 12(13): 3262-3272, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38456357

RESUMO

Traditional petroleum-based plastics have high energy consumption, require professional equipment, are non-degradable after use, and lack antibacterial properties, making it impossible to achieve long-lasting freshness in fruits and vegetables. Herein, we report a novel co-type film-forming method with low energy consumption and without production equipment, which uses PVA-borax gel as a substrate and adds a certain proportion of CMC and TA to prepare multifunctional CMC/TA@PVA-borax composite hydrogels (CTPB). The dynamic borax ester bonding and hydrogen bonding in the CTPB hydrogel results in an ultra-high tensile strength of more than 5500% and rapid self-healing within 8 s. Interestingly, hydrogels can be arbitrarily shaped and stretched like play dough and thus can be stretched into ductile films by co-type film formation. The antimicrobial properties of the hydrogel film can be attributed to the synergistic effects of TA and borax. The mussel structure of TA allows the hydrogel film to adhere directly to different surfaces for more effective bacterial killing. In addition, the hydrogel film has a high level of biosafety and biodegradability and shows good performance in fruit storage. This study provides a convenient and low-energy method for the preparation of films, which in part reduces the increasing environmental pollution caused by petroleum-based plastics.


Assuntos
Boratos , Frutas , Petróleo , Resistência à Tração , Álcool de Polivinil/química , Hidrogéis/química , Plásticos
4.
An Acad Bras Cienc ; 96(1): e20230092, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511742

RESUMO

Poly(vinyl alcohol) (PVOH) is a water-soluble polymer having a hydroxyl group as a functional group contributing to excellent membrane-forming and mechanical performance. PVOH is obtained by the hydrolysis of polyvinyl acetate, and its physical properties are affected by its degree of hydrolysis, whether, partial or complete. In this study, PVOH hydrogels were synthesized by a solution under stirring and heating techniques with citric (AC) and tartaric acids (AT) crosslinker agents, with different time reactions of 20 min.; 1; 2, and 3 h were investigated. These samples were characterized by the kinetics of water uptake, gel fraction, thermal analysis, and physical-chemical analysis, and their structure was elucidated. The results obtained have shown chemical modification by organic acids and improved the properties to good thermal stability and swelling to AT hydrogels up to 900% water uptake. In the gel fraction, the samples' esterification was shown and verified by FTIR spectra. To AC hydrogels the chemical modification was low due to the steric hindrance, which caused disintegration of the hydrogel in swelling and gel fraction test, but with absorption in the moisture test performed. The incorporation and effects of citric and tartaric acids enable the development of new hydrogel systems, with specific properties.


Assuntos
Hidrogéis , Álcool de Polivinil , Álcool de Polivinil/química , Tempo de Reação , Hidrogéis/química , Água
5.
Sci Rep ; 14(1): 7356, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548906

RESUMO

Packaging is very important to maintain the quality of food and prevent the growth of microbes. Therefore, the use of food packaging with antimicrobial properties protects the food from the growth of microorganisms. In this study, antibacterial nanocomposite films of polyvinyl alcohol/starch/chitosan (PVA/ST/CS) together with nickel oxide-copper oxide nanoparticles (NiO-CuONPs) are prepared for food packaging. NiO-CuONPs were synthesized by the co-precipitation method, and structural characterization of nanoparticles (NPs) was carried out by XRD, FTIR, and SEM techniques. Composites of PVA/ST/CS, containing different percentages of NPs, were prepared by casting and characterized by FTIR and FESEM. The mechanical properties, diffusion barrier, and thermal stability were determined. The nanoparticles have a round structure with an average size of 6.7 ± 1.2 nm. The cross-section of PVA/ST/CS film is dense, uniform, and without cracks. In the mechanical tests, the addition of NPs up to 1% improved the mechanical properties (TS = 31.94 MPa), while 2% of NPs lowered TS to 14.76 MPa. The fibroblast cells toxicity and the films antibacterial activity were also examined. The films displayed stronger antibacterial effects against Gram-positive bacteria (Staphylococcus aureus) compared to Gram-negative bacteria (Escherichia coli). Furthermore, these films have no toxicity to fibroblast cells and the survival rate of these cells in contact with the films is more than 84%. Therefore, this film is recommended for food packaging due to its excellent mechanical and barrier properties, good antibacterial activity, and non-toxicity.


Assuntos
Quitosana , Nanopartículas , Quitosana/farmacologia , Quitosana/química , Embalagem de Alimentos/métodos , Álcool de Polivinil/química , Amido , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas/química
6.
Int J Pharm ; 654: 123968, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38460771

RESUMO

Wound healing constitutes a formidable challenge within the healthcare system, attributable to infection risks and protracted recovery periods. The pressing need for innovative wound healing methods has spurred the urgency to develop novel approaches. This study sought to advance wound healing by introducing a novel approach employing a composite sponge dressing. The composite sponge dressing, derived from LFL-ZnO (synthesized through the green methodology utilizing Lactobacillus plantarum ZDY2013 fermentation liquid), polyvinyl alcohol (PVA), and sodium alginate (SA) via a freeze-thaw cycle and freeze-drying molding process, demonstrated notable properties. The findings elucidate the commendable swelling, moisturizing, and mechanical attributes of the SA/LFL-ZnO/PVA composite sponge dressing, characterized by a porous structure. Remarkably, the dressing incorporating LFL-ZnO exhibited substantial inhibition against both methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus (S. aureus). Hemolysis and cytotoxicity tests corroborated the excellent biocompatibility of the sponge dressing. In vivo evaluation of the therapeutic efficacy of the 1 mg/mL LFL-ZnO composite dressing on scald wounds and S. aureus-infected wounds revealed its capacity to accelerate wound healing and exert pronounced antibacterial effects. Consequently, the composite sponge dressings synthesized in this study hold significant potential for application in wound treatment.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Óxido de Zinco , Álcool de Polivinil/química , Óxido de Zinco/química , Staphylococcus aureus , Alginatos/química , Bandagens/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis/química , Cicatrização
7.
Int J Biol Macromol ; 264(Pt 2): 130727, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460645

RESUMO

Enormous amounts of food resources are annually wasted because of microbial contamination, highlighting the critical role of effective food packaging in preventing such losses. However, traditional food packaging faces several limitations, such as low mechanical strength, poor fatigue resistance, and low water retention. In this study, we aimed to prepare nanocellulose hydrogels with enhanced stretchability, fatigue resistance, high water retention, and antibacterial properties using soy hull nanocellulose (SHNC), polyvinyl alcohol (PVA), sodium alginate (SA), and tannic acid (TA) as raw materials. These hydrogels were applied in food packaging to extend the shelf life of refrigerated chicken. The structure and properties (e.g., mechanical, antibacterial, and barrier properties) of these hydrogels were characterized using different techniques. Fourier-transform infrared spectroscopy revealed the presence of hydrogen and ester bonds in the hydrogels, whereas scanning electron microscopy revealed the three-dimensional network structure of the hydrogels. Mechanical testing demonstrated that the SHNC/PVA/SA/TA-2 hydrogel exhibited excellent tensile properties (elongation = 160 %), viscoelasticity (storage modulus of 1000 Pa), and mechanical strength (compressive strength = 10 kPa; tensile strength = 0.35 MPa). Moreover, under weak acidic and alkaline conditions, the ester bonds of the hydrogel broke down with an increase in pH, improving its swelling and release properties. The SHNC/PVA/SA/TA-2 hydrogel displayed an equilibrium swelling ratio exceeding 300 %, with a release rate of >80 % for the bioactive substance TA. Notably, antibacterial testing showed that the SHNC/PVA/SA/TA-2 hydrogel effectively deactivated Staphylococcus aureus and Escherichia coli, prolonging the shelf life of refrigerated chicken to 10 d. Therefore, the SHNC/PVA/SA/TA hydrogels can be used in food packaging to extend the shelf life of refrigerated meat products. Their cost-effectiveness and simple preparation make them suitable for various applications in the food industry.


Assuntos
Galinhas , Hidrogéis , Polifenóis , Animais , Hidrogéis/farmacologia , Hidrogéis/química , Antibacterianos/farmacologia , Antibacterianos/química , Água , Ésteres , Álcool de Polivinil/farmacologia , Álcool de Polivinil/química
8.
Colloids Surf B Biointerfaces ; 237: 113868, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522282

RESUMO

Silver nanoparticles (AgNPs) is an excellent antibacterial agent, which is widely used in medical, food, environmental and other fields, but AgNPs are easy to accumulate in aqueous solution, so their application in various fields is limited. Therefore, it is particularly important to propose a new application method or to prepare a new composite material. In this study, OA/PVA was obtained by cross-linking oxalic acid (OA) with polyvinyl alcohol (PVA). Then Ag/NCC was obtained by in situ reduction of AgNPs on nanocellulose crystals (NCC). Finally, Ag/NCC/OA/PVA composite antimicrobial films with good waterproofing effect were prepared by mixing Ag/NCC with OA/PVA. Subsequently, the films were characterized using SEM, UV-vis, FTIR and XRD, as well as physicochemical properties such as mechanical strength and hydrophilic properties were determined. The results indicated that the Ag/NCC/OA/PVA films possess good light transmittance, mechanical properties, water resistance, antibacterial activity, and biodegradability. The results of the mechanism study showed that Ag/NCC/OA/PVA films can destroy cell integrity, inhibit succinate dehydrogenase (SDH) activity, thereby reducing intracellular ATP levels. And induce a large number of reactive oxygen species (ROS) production, eventually leading to the death of C. sakazakii. In summary, Ag/NCC/OA/PVA film has good physical and chemical properties, antibacterial activity and biocompatibility, and has promising applications in food and medical antibacterial fields.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Prata/farmacologia , Prata/química , Álcool de Polivinil/química , Nanopartículas Metálicas/química , Ácido Oxálico/farmacologia , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Biofilmes
9.
Talanta ; 272: 125789, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428130

RESUMO

Moving towards green chemistry to minimize the diverse effect of chemicals on human health and environment has become a great issue in chemistry. On the other hand, determination of pharmaceuticals is an important issue for both human health and environment. In this regard two natural and benign compounds such as quercetin a polyphenolic flavonoid and Arabic Gum (AG) a polysaccharide were used to construct a sensor for meropenem. Herein, a new method was established for the synthesis of AG and polyvinyl alcohol (PVA) composite decorated by quercetin nanoparticles (QUENPs) as a fluorimetric film sensor to measure meropenem. In order to embed QUENPs in the polymer composite substrate, first QUENPs were synthesized and then added to the prepared composite solution under optimal conditions. The characteristics of AG and PVA composite (AG-PVA) and AG-PVA composite decorated by QUENPs films (QUENPs-AG-PVA), before and after the addition of meropenem was studied by TEM, FT-IR and EDX-Mapping. The developed film sensor was placed in a holder made with 3D printer. The difference in the fluorescence intensity of the fabricated film before and after the addition of meropenem was taken as the signal for measuring meropenem. The effect of different parameters on the fabrication of film fluorimetric sensor such as the concentration of polymer solutions, the volume of QUENPs and the volume of glycerol were investigated. Factors affecting the measurement of meropenem such as pH, type of buffer, volume of meropenem solution added on the sensor and time were also investigated. Under the obtained optimum conditions, the calibration graph was linear in the concentration range of 50-800 ng mL-1 with a correlation coefficient (r) of 0.9976 and the detection limit was 42.6 ng mL-1. The relative standard deviation was 3.5% and 1.4%, for eight replicate determinations of 100 ng mL-1 and 400 ng mL-1 of meropenem, respectively. The proposed method was successfully utilized for determination of meropenem in blood serum, human urine and pharmaceutical samples.


Assuntos
Nanopartículas , Álcool de Polivinil , Humanos , Álcool de Polivinil/química , Meropeném , Quercetina , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química , Polímeros
10.
Int J Biol Macromol ; 263(Pt 1): 130513, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428758

RESUMO

Anthocyanins (ACNs) are natural compounds with potential applications due to their colorimetric response to pH. Due to their sensitivity to various environmental factors, nanoencapsulation with biopolymers is a successful strategy for stabilizing ACNs. In this work ACNs were extracted from grape skins and encapsulated into chitosan (CS) nanoparticles by ionic gelation using sodium tripolyphosphate (TPP) as a cross-linking agent. CS nanoparticles loaded with ACNs had particle sizes between 291 and 324 nm and polydispersity index around 0.3. The encapsulation efficiency of ACNs was approximately 60 %; and encapsulated anthocyanins (ACN-NPs) exhibited color change properties under different pH conditions. pH-sensitive labels based on polyvinyl alcohol (PVA) were prepared by the casting method. The effect of incorporating ACN-NPs on the physical, structural, and pH-sensitive properties of PVA labels was evaluated, and its application as shrimp freshness indicator was studied. The nanoencapsulation protected ACNs against heat and light treatments, preserving the original purple color. When applying the label, visible changes from red to blue until reaching yellow were observed with the change in the quality of the shrimp at the refrigeration temperature. The results suggest that PVA labels containing ACNs encapsulated in C-NPs can be used as smart packaging labels in the food industry.


Assuntos
Quitosana , Nanopartículas , Vitis , Quitosana/química , Álcool de Polivinil/química , Antocianinas/química , Nanopartículas/química , Extratos Vegetais/química , Embalagem de Alimentos/métodos , Concentração de Íons de Hidrogênio
11.
J Mater Chem B ; 12(16): 3917-3926, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38536012

RESUMO

The repair capacity of skeletal muscle is severely diminished in massive skeletal muscle injuries accompanied by inflammation, resulting in muscle function loss and scar tissue formation. In the current work, we developed a tannic acid (TA)- and silicate ion-functionalized tissue adhesive poly(vinyl alcohol) (PVA)-starch composite hydrogel, referred to as PSTS (PVA-starch-TA-SiO32-). It was formed based on the hydrogen bonding of TA to organic polymers, as well as silicate-TA ligand interaction. PSTS could be gelatinized in minutes at room temperature with crosslinked network formation, making it applicable for injection. Further investigations revealed that PSTS had skeletal muscle-comparable conductivity and modulus to act as a temporary platform for muscle repairing. Moreover, PSTS could release TA and silicate ions in situ to inhibit bacterial growth, induce vascularization, and reduce oxidation, paving the way to the possibility of creating a favorable microenvironment for skeletal muscle regeneration and tissue fibrosis control. The in vivo model confirmed that PSTS could enhance muscle fiber regeneration and myotube formation, as well as reduce infection and inflammation risk. These findings thereby implied the great potential of PSTS in the treatment of formidable skeletal muscle injuries.


Assuntos
Hidrogéis , Músculo Esquelético , Polifenóis , Álcool de Polivinil , Silicatos , Amido , Taninos , Taninos/química , Taninos/farmacologia , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , Músculo Esquelético/efeitos dos fármacos , Animais , Amido/química , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogéis/síntese química , Silicatos/química , Silicatos/farmacologia , Camundongos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
12.
Int J Biol Macromol ; 264(Pt 1): 130469, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458007

RESUMO

Facial mask substrates commonly used in skincare are often considered unhealthy and environmentally unfriendly due to their composition of premoistened nonwovens containing various preservatives. This study aims to address this issue by developing a preservative-free degradable aerogel made from polyvinyl alcohol (PVA)/pullulan (PUL) using a unidirectional freeze-drying method. The aerogels had ordered three-dimensional porous structures and exhibited desirable mechanical properties. They were soft and flexible in both dry and wet states, and their Young's moduli were comparable to that of human skin. The aerogels had high porosity, ranging from 93.0 % to 95.1 %, and exhibited a high water absorption rate and water absorption capacity (ranging from 7.5 g/g to 10.1 g/g). After 30 min of water evaporation, the aerogels showed excellent moisture retention, ranging from 88 % to 93 %. Additionally, the PVA/PUL aerogel efficiently loaded and released active ingredients, such as rapidly releasing ascorbic acid (> 90 % within 30 min). These findings suggest that the PVA/PUL aerogel has potential as a material for facial mask substrates.


Assuntos
Álcool de Polivinil , Água , Humanos , Álcool de Polivinil/química , Glucanos , Porosidade
13.
Science ; 383(6690): 1492-1498, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38547269

RESUMO

Transient implantable piezoelectric materials are desirable for biosensing, drug delivery, tissue regeneration, and antimicrobial and tumor therapy. For use in the human body, they must show flexibility, biocompatibility, and biodegradability. These requirements are challenging for conventional inorganic piezoelectric oxides and piezoelectric polymers. We discovered high piezoelectricity in a molecular crystal HOCH2(CF2)3CH2OH [2,2,3,3,4,4-hexafluoropentane-1,5-diol (HFPD)] with a large piezoelectric coefficient d33 of ~138 picocoulombs per newton and piezoelectric voltage constant g33 of ~2450 × 10-3 volt-meters per newton under no poling conditions, which also exhibits good biocompatibility toward biological cells and desirable biodegradation and biosafety in physiological environments. HFPD can be composite with polyvinyl alcohol to form flexible piezoelectric films with a d33 of 34.3 picocoulombs per newton. Our material demonstrates the ability for molecular crystals to have attractive piezoelectric properties and should be of interest for applications in transient implantable electromechanical devices.


Assuntos
Materiais Biocompatíveis , Compostos Férricos , Polímeros , Biodegradação Ambiental , Polímeros/química , Polímeros/metabolismo , Álcool de Polivinil/química , Álcool de Polivinil/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Eletricidade , Animais , Ratos , Ratos Sprague-Dawley , Compostos Férricos/química , Compostos Férricos/metabolismo
14.
Int J Biol Macromol ; 265(Pt 2): 130981, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38513894

RESUMO

High-value utilization of bleached lignin has been widely used in different fields, whereas the investigation on darkened lignin in composite materials was often ignored. In this work, a sort of eco-friendly and structurally robust sodium carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA)/sodium lignosulfonate (SLS) black composite mulch film was elaborately designed. The chelation and redox reaction effect between Fe ions and SLS lead to the formation of a more quinones structure on lignin, darkening both lignin and the mulch films. The chelation effect between Fe ions and biopolymer formed three-dimensional structures, which can be used as sacrifice bonds to dissipate energy and improve the mechanical properties of the composite films. In particular, the maximum elongation at break and toughness increased from 48.4 % and 1141 kJ/m3 for the CMC/PVA film to 210.9 % and 1426 kJ/m3 for the optimized CMC/PVA/SLS/Fe black mulch film, respectively. In addition, the optimized black mulch film also possesses good soil water retention, thermal preservation effect, controlled urea release, and well biodegradability. This work offered a novel strategy for designing eco-friendly black mulch with reinforced mechanical strength, slow-release urea, soil moisture retention, and heat preservation performances.


Assuntos
Ferro , Lignina , Agricultura/métodos , Solo , Álcool de Polivinil/química , Ureia , Sódio
15.
Int J Biol Macromol ; 265(Pt 1): 130792, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479670

RESUMO

The curdlan gel is a natural material produced by bacteria. It utilizes chemical cross-linking reactions to form a 3D porous composite hydrogel, increasing its porosity and water content, and improving its mechanical properties. It can be used in tissue repair and regenerative medicine. Curdlan-Poly(vinyl alcohol) (PVA) composite hydrogel can rapidly swell within 1 min due to its porous structure. Compression tests confirmed that it still maintains its original mechanical strength, even after five repeated freeze-thaw (FT) processes, making it suitable for long-term cryopreservation. The purpose of this study is to transplant umbilical cord mesenchymal stem cells (UC-MSCs) on Curdlan-PVA composite hydrogel and observe the chondrocytes on the material. The results of using 4',6-diamidino-2-phenylindole (DAPI), hematoxylin and eosin (H&E), calcein-acetoxymethyl ester (calcein AM), and Collagen type II-Fluorescein isothiocyanate (FITC) staining, confirmed that UC-MSCs can attach and differentiate into chondrocytes on 3D Curdlan-PVA composite hydrogel.


Assuntos
Hidrogéis , Células-Tronco Mesenquimais , beta-Glucanas , Hidrogéis/farmacologia , Hidrogéis/química , Álcool de Polivinil/química , Congelamento , Condrogênese , Materiais Biocompatíveis/química , Etanol
16.
Int J Biol Macromol ; 265(Pt 1): 130858, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490398

RESUMO

Electrospinning has been acknowledged as an efficient technique for the fabrication of continuous nanofibers from polymeric based materials such as polyvinyl alcohol (PVA), cellulose acetate (CA), chitin nanocrystals and others. These nanofibers exhibit chemical and mechanical stability, high porosity, functionality, high surface area and one-dimensional orientation which make it extremely beneficial in industrial application. In recent years, research on chitin - a biopolymer derived from crustacean and fungal cell wall - had gained interest due to its unique structural arrangement, excellent physical and chemical properties, in which make it biodegradable, non-toxic and biocompatible. Chitin has been widely utilized in various applications such as wound dressings, drug delivery, tissue engineering, membranes, food packaging and others. However, chitin is insoluble in most solvents due to its highly crystalline structure. An appropriate solvent system is required for dissolving chitin to maximize its application and produce a fine and smooth electrospun nanofiber. This review focuses on the preparation of chitin polymer solution through dissolution process using different types of solvent system for electrospinning process. The effect of processing parameters also discussed by highlighting some representative examples. Finally, the perspectives are presented regarding the current application of electrospun chitin nanofibers in selected fields.


Assuntos
Quitina , Engenharia Tecidual , Quitina/química , Engenharia Tecidual/métodos , Polímeros , Álcool de Polivinil/química , Solventes
17.
J Mater Chem B ; 12(12): 3079-3091, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38444266

RESUMO

Traditional hydrogels are usually weak and brittle, which limit their application in articular cartilage replacement because cartilage is generally strong, tough, and elastic in nature. Therefore, it is highly desirable to construct hydrogels to mimic the mechanical properties of the native articular cartilage. Herein, in this work, poly(vinyl alcohol)/polyacrylamide (PVA/PAM) DN hydrogels were prepared by in situ polymerization, which were then treated with Hofmeister series ions (Cit3-, SO42-, and Cl-) to achieve H-PVA/PAM DN hydrogels. Among the three Hofmeister ions, the DN hydrogel treated with Cit3- (named PVA/PAM-Cit) showed the densest microstructure and the highest crystallinity degree. In this context, PVA/PAM-Cit exhibited a tensile strength of 18.9 ± 1.6 MPa, a compressive strength of 102.3 ± 7.9 MPa, a tensile modulus of 10.6 ± 2.1 MPa, a compressive modulus of 8.9 ± 0.8 MPa, and a roughness of 66.2 ± 4.2 MJ m-3, respectively, which were the highest strength and modulus, and the second highest toughness when compared with those of the reported PVA and PVA based DN hydrogels so far. It also showed an extreme high elasticity, which could maintain a stress of 99.2% after 500 cycles of fatigue testing. Additionally, PVA/PAM-Cit can promote the adhesion, spreading and proliferation of chondrocytes. These results verify that such a strong, tough, and elastic hydrogel could be a novel candidate material for articular cartilage replacement.


Assuntos
Resinas Acrílicas , Cartilagem Articular , Álcool de Polivinil/química , Etanol , Hidrogéis/química , Íons
18.
Int J Pharm ; 654: 123928, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38401874

RESUMO

An important part of wound healing is providing effective wound care, coupled with preventing wound infection, which slows or disrupts healing. There are currently many herbal plants that have historical supernatural properties that show remarkable wound healing abilities. These herbal extracts have shown promising results when applied to electrospun nanofibrous mats platforms for wound healing. Accordingly, Malva Sylvestris extract (MS) was electrospun into polyvinyl alcohol/alginate nanofibrous mats (PVA/ALG). Field Emission Scanning Electron Microscopy (FESEM) demonstrated that the fiber diameter ranged from approximately 100-200 nm in nanofibrous mats, with a uniform appearance without beads. MS extract was detected in nanofibrous mats by Fourier Transform Infrared Spectroscopy (FTIR). A major benefit of incorporating MS extract into PVA/ALG nanofibrous mats is that their alterations have resulted in enhanced mechanical characteristics. The nanofibrous mats containing MS extracts showed significantly increased antibacterial efficacy against Gram-positive and Gram-negative bacteria. Based on the findings from in vivo experiments, the PVA/ALG/MS1 (M2) dressing demonstrated a wound closure rate of 93-94 % within 21 days of treatment in rats, indicating its significant potential for use as a wound dressing agent in the treatment of burn injuries. The combination of PVA, ALG, and MS1 in this nanofibrous mats exhibited beneficial properties, including biocompatibility, suitable mechanical strength, and the ability to promote cellular proliferation and angiogenesis, further validating its effectiveness as a wound healing dressing.


Assuntos
Malva , Nanofibras , Ratos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Álcool de Polivinil/química , Alginatos/química , Nanofibras/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Etanol , Extratos Vegetais/farmacologia
19.
Food Chem ; 443: 138506, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38306905

RESUMO

Researchers are addressing environmental concerns related to petroleum-based plastic packaging by exploring biopolymers from natural sources, chemical synthesis, and microbial fermentation. Despite the potential of individual biopolymers, they often exhibit limitations like low water resistance and poor mechanical properties. Blending polymers emerges as a promising strategy to overcome these challenges, creating films with enhanced performance. This review focuses on recent advancements in chitosan/polyvinyl alcohol (PVA) blend food packaging films. It covers molecular structure, properties, strategies for performance improvement, and applications in food preservation. The blend's excellent compatibility and intermolecular interactions make it a promising candidate for biodegradable films. Future research should explore large-scale thermoplastic technologies and investigate the incorporation of additives like natural extracts and nanoparticles to enhance film properties. Chitosan/PVA blend films offer a sustainable alternative to petroleum-based plastic packaging, with potential applications in practical food preservation.


Assuntos
Quitosana , Petróleo , Álcool de Polivinil/química , Quitosana/química , Embalagem de Alimentos , Biopolímeros/química
20.
Biomed Mater ; 19(2)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38364288

RESUMO

In this work, the semi solid extrusion 3D printing process was utilized to incorporate anti-HIV drug Dolutegravir and its nanoparticles into the buccal film (BF) that was fabricated using the developed polymer ink. The composite made of polyvinyl alcohol (PVA) and sodium alginate was processed into a 3D printing polymer ink with optimum viscosity (9587 ± 219 cP) needed for the seamless extrusion through the nozzle of the 3D printer. The formulated BFs were assessed for its physical properties like weight (0.414 ± 0.3 g), thickness (1.54 ± 0.02 mm), swelling index (18.5 ± 0.91%), and mucoadhesiveness strength (0.165 ± 0.09 N) etc, The structural integrity and the surface morphology of the developed BFs were investigated by scanning electron microscopy analysis. The chemical stability and the solid-state nature of the drug in the BFs were assessed by Fourier transform infrared and x-ray diffraction analysis respectively. Further the BFs were assessed for drug dissolutionin-vitroandex-vivo, to study the effect of polymer composition and printing condition on the dissolution profile of the drug in the simulated salivary fluid. The results demonstrated that the developed PVA based polymer ink for 3D printing utilizing pressure is a versatile approach in the context of manufacturing mucoadhesive BFs customized in terms of shape and the amount of drug loaded.


Assuntos
Quitosana , Compostos Heterocíclicos com 3 Anéis , Nanopartículas , Oxazinas , Piperazinas , Piridonas , Humanos , Criança , Quitosana/química , Polímeros/química , Álcool de Polivinil/química , Impressão Tridimensional
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