-
Frontiers in Chemistry 2024Polyvinyl alcohol (PVA) hydrogel is favored by researchers due to its good biocompatibility, high mechanical strength, low friction coefficient, and suitable water... (Review)
Review
Polyvinyl alcohol (PVA) hydrogel is favored by researchers due to its good biocompatibility, high mechanical strength, low friction coefficient, and suitable water content. The widely distributed hydroxyl side chains on the PVA molecule allow the hydrogels to be branched with various functional groups. By improving the synthesis method and changing the hydrogel structure, PVA-based hydrogels can obtain excellent cytocompatibility, flexibility, electrical conductivity, viscoelasticity, and antimicrobial properties, representing a good candidate for articular cartilage restoration, electronic skin, wound dressing, and other fields. This review introduces various preparation methods of PVA-based hydrogels and their wide applications in the biomedical field.
PubMed: 38435666
DOI: 10.3389/fchem.2024.1376799 -
Materials (Basel, Switzerland) Dec 2023Plastics have recently become an indispensable part of everyone's daily life due to their versatility, durability, light weight, and low production costs. The increasing... (Review)
Review
Plastics have recently become an indispensable part of everyone's daily life due to their versatility, durability, light weight, and low production costs. The increasing production and use of plastics poses great environmental problems due to their incomplete utilization, a very long period of biodegradation, and a negative impact on living organisms. Decomposing plastics lead to the formation of microplastics, which accumulate in the environment and living organisms, becoming part of the food chain. The contamination of soils and water with poly(vinyl chloride) (PVC) seriously threatens ecosystems around the world. Their durability and low weight make microplastic particles easily transported through water or air, ending up in the soil. Thus, the problem of microplastic pollution affects the entire ecosystem. Since microplastics are commonly found in both drinking and bottled water, humans are also exposed to their harmful effects. Because of existing risks associated with the PVC microplastic contamination of the ecosystem, intensive research is underway to develop methods to clean and remove it from the environment. The pollution of the environment with plastic, and especially microplastic, results in the reduction of both water and soil resources used for agricultural and utility purposes. This review provides an overview of PVC's environmental impact and its disposal options.
PubMed: 38204025
DOI: 10.3390/ma17010173 -
Gels (Basel, Switzerland) Sep 2023This study aims to analyze the physical-mechanical properties and dynamic models of tissue-simulating hydrogels, specifically the photoacoustic (PA) response signals, by...
This study aims to analyze the physical-mechanical properties and dynamic models of tissue-simulating hydrogels, specifically the photoacoustic (PA) response signals, by varying the concentrations of polyvinyl alcohol (PVA) and molecular weight (MW). A state-space model (SSM) is proposed to study the PVA hydrogels to retrieve the PA-related signal's damping ratio and natural frequency. Nine box-shaped PVA hydrogels containing saline solution were used, with five concentrations of PVA (7, 9, 12, 15, 20%) for MW1 and four for MW2. The results indicated that the concentration of PVA and MW played an important role in the PA wave's amplitude, arrival time, and speed of sound over the hydrogels. The SSM parameters showed that increasing PVA and MW concentrations improved the hydrogels' ability to absorb and transfer energy under the PA effect. These parameters were also found to be correlated with density and modulus of elasticity. Additionally, the concentrations of PVA and MW affected the absorption and optical scattering coefficients. The physical-mechanical properties, including porosity, density, and modulus of elasticity, improved as the concentration of PVA and MW increased. The ultimate goal of this study is to develop hydrogels as phantoms that can be used for tissue simulation and imaging.
PubMed: 37754408
DOI: 10.3390/gels9090727 -
Polymers Jul 2023We fabricated new hydrogels using polyvinyl alcohol (PVA) and succinoglycan (SG) directly isolated and obtained from Rm 1021 via the freeze-thaw method. Both the...
We fabricated new hydrogels using polyvinyl alcohol (PVA) and succinoglycan (SG) directly isolated and obtained from Rm 1021 via the freeze-thaw method. Both the composition of the hydrogels and the freeze-thaw cycles were optimized to maximize the swelling ratio for the preparation of the PVA/SG hydrogels. During the optimization process, the morphology and conformational change in the hydrogel were analyzed by scanning electron microscopy, rheological measurements, and compressive tests. An optimized hydrogel with a maximum swelling ratio of 17.28 g/g was obtained when the composition of PVA to SG was 50:50 (PVA/SG 50/50) and the total number of freeze-thaw cycles was five. The PVA/SG 50/50 hydrogel had the largest pore with 51.24% porosity and the highest cross-over point (28.17%) between the storage modulus (G') and the loss modulus (G″). The PVA/SG 50/50 hydrogel showed improved thermal stability owing to its interaction with thermally stable SG chains. The improvement in the thermal stability was confirmed by thermogravimetric analysis and differential scanning calorimetry. In addition, the PVA/SG 50/50 hydrogel showed differential drug release according to the corresponding pH under acidic conditions of pH 1.2 and slightly basic conditions of pH 7.4. Furthermore, the cell viability test on the HEK-293 cell line for that hydrogel demonstrated that the PVA/SG 50/50 hydrogel was non-toxic and biocompatible. Therefore, this hydrogel could be a potential scaffold capable of pH-responsive drug delivery for chronic wound dressing applications.
PubMed: 37514399
DOI: 10.3390/polym15143009 -
Membranes Aug 2023The incorporation of different functional fillers has been widely used to improve the properties of polymeric materials. The polyhydroxy structure of PVA with excellent... (Review)
Review
The incorporation of different functional fillers has been widely used to improve the properties of polymeric materials. The polyhydroxy structure of PVA with excellent film-forming ability can be easily combined with organic/inorganic multifunctional compounds, and such an interesting combining phenomenon can create a variety of functional materials in the field of materials science. The composite membrane material obtained by combining MOF material with high porosity, specific surface area, and adjustable structure with PVA, a non-toxic and low-cost polymer material with good solubility and biodegradability, can combine the processability of PVA with the excellent performance of porous filler MOFs, solving the problem that the poor machinability of MOFs and the difficulty of recycling limit the practical application of powdered MOFs and improving the physicochemical properties of PVA, maximizing the advantages of the material to develop a wider range of applications. Firstly, we systematically summarize the preparation of MOF/PVA composite membrane materials using solution casting, electrostatic spinning, and other different methods for such excellent properties, in addition to discussing in detail the various applications of MOF/PVA composite membranes in water treatment, sensing, air purification, separation, antibacterials, and so on. Finally, we conclude with a discussion of the difficulties that need to be overcome during the film formation process to affect the performance of the composite film and offer encouraging solutions.
PubMed: 37755178
DOI: 10.3390/membranes13090755 -
Frontiers in Immunology 2023The release of nanoplastics (NPs) in the environment is a significant health concern for long-term exposed humans. Although their usage has certainly revolutionized...
The release of nanoplastics (NPs) in the environment is a significant health concern for long-term exposed humans. Although their usage has certainly revolutionized several application fields, at nanometer size, NPs can easily interact at the cellular level, resulting in potential harmful effects. Micro/Nanoplastics (M/NPs) have a demonstrated impact on mammalian endocrine components, such as the thyroid, adrenal gland, testes, and ovaries, while more investigations on prenatal and postnatal exposure are urgently required. The number of literature studies on the NPs' presence in biological samples is increasing. However, only a few offer a close study on the model environmental NP-immune system interaction exploited by advanced microscopy techniques. The present study highlights substantial morphological and lipid metabolism alterations in human M1 macrophages exposed to labeled polypropylene and polyvinyl chloride nanoparticles (PP and PVC NPs) (20 μg/ml). The results are interpreted by advanced microscopy techniques combined with standard laboratory tests and fluorescence microscopy. We report the accurate detection of polymeric nanoparticles doped with cadmium selenide quantum dots (CdSe-QDs NPs) by following the Se (L line) X-ray fluorescence emission peak at higher sub-cellular resolution, compared to the supportive light fluorescence microscopy. In addition, scanning transmission X-ray microscopy (STXM) imaging successfully revealed morphological changes in NP-exposed macrophages, providing input for Fourier transform infrared (FTIR) spectroscopy analyses, which underlined the chemical modifications in macromolecular components, specifically in lipid response. The present evidence was confirmed by quantifying the lipid droplet (LD) contents in PP and PVC NPs-exposed macrophages (0-100 μg/ml) by Oil Red O staining. Hence, even at experimental NPs' concentrations and incubation time, they do not significantly affect cell viability; they cause an evident lipid metabolism impairment, a hallmark of phagocytosis and oxidative stress.
Topics: Humans; Animals; Female; Pregnancy; Microplastics; Lipid Metabolism; Synchrotrons; Macrophages; Microscopy, Fluorescence; Mammals
PubMed: 37744340
DOI: 10.3389/fimmu.2023.1247747 -
Optics Express Oct 2023This research investigates the hybridized plasmonic response of silver film combined with dispersed silver (Ag) nanowires (NWs) to random laser emission. The mixture of...
This research investigates the hybridized plasmonic response of silver film combined with dispersed silver (Ag) nanowires (NWs) to random laser emission. The mixture of Rhodamine B (RhB) dye and polyvinyl alcohol (PVA) matrix is taken as the gain medium for random lasing, and the silver combination provides feedback mechanisms for light trapping. Importantly, film roughness and the coupling between localized and extended (delocalized) surface plasmons play a vital role in RL performance evaluation. The laser threshold is strongly influenced by film thickness attributed to surface roughness. Furthermore, the variation in film thickness also supports the wavelength modulation of 9 nm (597 nm to 606 nm), which results from the reabsorption of RhB. Additionally, the intriguing capability of emission wavelength tuning under the variation of temperature facilitates exciting prospects for precise wavelength control in plasmonic devices.
PubMed: 38017770
DOI: 10.1364/OE.503031 -
The Science of the Total Environment Jul 2024Personal Care Products (PCPs) have been one of the most studied chemicals in the last twenty years since they were identified as pseudo-persistent pollutants by the...
Personal Care Products (PCPs) have been one of the most studied chemicals in the last twenty years since they were identified as pseudo-persistent pollutants by the European Union in the early 2000s. The accumulation of PCPs in the aquatic environment and their effects on non-target species make it necessary to find new, less harmful, substances. Polyethylene glycol (PEGs) and polyvinyl alcohol (PVAs) are two polymers that have increased their presence in the composition of PCPs in recent years, but little is known about the effect of their accumulation in the environment on non-target species. Through embryotoxicity tests on two common models of aquatic organisms (Danio rerio and Xenopus laevis), this work aims to increase the knowledge of PEGs and PVAs' effects on non-target species. Animals were exposed to the pollutant for 96 h. The main embryotoxicity endpoint (mortality, hatching, malformations, heartbeat rate) was recorded every 24 h. The most significant results were hatching delay in Danio rerio exposed to both chemicals, in malformations (oedema, body malformations, changes in pigmentation and deformations of spine and tail) in D. rerio and X. laevis and significant change in the heartbeat rate (decrease or increase in the rate) in both animals for all chemicals tested.
Topics: Animals; Zebrafish; Water Pollutants, Chemical; Embryo, Nonmammalian; Polyvinyl Alcohol; Polyethylene Glycols; Xenopus laevis; Toxicity Tests
PubMed: 38735322
DOI: 10.1016/j.scitotenv.2024.173154 -
Chemosphere Dec 2023Atmospheric microplastics (MPs) have been sampled from coastal southwest England during twelve periods over a 42-day timeframe in late autumn. MPs were dominated by...
Atmospheric microplastics (MPs) have been sampled from coastal southwest England during twelve periods over a 42-day timeframe in late autumn. MPs were dominated by fibres, with foams, fragments and pellets also observed. The majority of fibres were identified as the semisynthetic polymer, rayon, while other shapes were dominated by various petroleum-based thermoplastics (including polyvinyl acetate, polyvinyl alcohol, polyamide and polyester) and paints. MP concentrations suspended in air ranged from 0.016 to 0.238 items per m but displayed no clear dependence on wind speed or direction. Total depositional fluxes ranged from 0.47 to 3.30 m h and showed no clear dependence on wind conditions or electrical conductivity of precipitation (as a measure of maritime influence). However, the concentration of deposited MPs in rainwater was inversely related to rainfall volume, suggesting that incipient precipitation acts to efficiently washout microplastics. A comparison of deposited and suspended MPs by size, shape and polymer type suggests that larger fibres constructed of rayon, polyamide and acrylic are preferentially removed from the atmosphere relative to smaller, non-fibrous MPs and particles constructed of polyester. A quantitative comparison of deposited and suspended MPs provided estimates of location- and environment-specific net settling velocities of between about 7 and 180 m h and corresponding residence times for an air column of 5000 m of between about 30 and 700 h. The findings of the study contribute to an improved understanding of the occurrence, transport and deposition of MPs in the atmosphere more generally.
Topics: Microplastics; Nylons; Plastics; Atmosphere; England; Polyesters; Polymers; Environmental Monitoring; Water Pollutants, Chemical
PubMed: 37751808
DOI: 10.1016/j.chemosphere.2023.140258 -
Molecules (Basel, Switzerland) Jul 2023In this study, propolis additives provide antibacterial and antifungal effects that prolong the product's shelf life. The aim of the study is to obtain homogeneous fiber...
In this study, propolis additives provide antibacterial and antifungal effects that prolong the product's shelf life. The aim of the study is to obtain homogeneous fiber membranes of polyvinyl alcohol and propolis by the electrospinning method and to evaluate their suitability for food packaging. Three propolis extracts are used in the study-water, ethyl alcohol, and glycerin-based. The membranes' morphology and fiber diameter distribution, tensile deformation, air permeability, thermogravimetric analysis, differential scanning calorimetry, Fourier-transform infrared spectroscopy, and microbiological tests (, , ) were analyzed for electrospun samples. The results of the study show that propolis extracts are incorporated into membranes and the additive provides an antimicrobial effect with the contact surface. The obtained membranes are breathable: gas exchange can be controlled by using a material of appropriate thickness (air permeability coefficient is 0.046 and 0.276 mm/s). The mechanical properties of membranes are affected by moisture, but tensile strength can be improved with thermal post-processing at 100 °C. The propolis-containing fibers' diameters are from 293 ± 8 to 664 ± 11 nm. Depending on membranes' demonstrated properties, it can be concluded that the composites have the potential to increase the shelf life of fresh fruits and berries.
Topics: Propolis; Food Packaging; Anti-Bacterial Agents; Tensile Strength; Edible Films
PubMed: 37513368
DOI: 10.3390/molecules28145497