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Methods in Molecular Biology (Clifton,... 2021Membrane arrays are a unique array platform option for the detection of multiple analytes or materials simultaneously. Their naturally absorptive properties and near...
Membrane arrays are a unique array platform option for the detection of multiple analytes or materials simultaneously. Their naturally absorptive properties and near universal use in various laboratory methods make it an excellent source with which to probe multiple factors simultaneously. Any liquid sample type can be probed, from bacterial strains, tissue lysates, secreted proteins, to DNA aptamers. Below, we will describe some considerations in how to print a membrane array and then a specific usage of the membrane arrays as it relates to a sandwich-based antibody array technique for simultaneously detection of secreted proteins in a liquid sample.
Topics: Absorption, Physicochemical; Collodion; Immunoblotting; Membranes, Artificial; Polyvinyls; Protein Array Analysis
PubMed: 33237414
DOI: 10.1007/978-1-0716-1064-0_11 -
Scientific Reports Dec 2022Hydrogel-encapsulated catalysts are an attractive tool for low-cost intensification of (bio)-processes. Polyvinyl alcohol-sodium alginate hydrogels crosslinked with...
Hydrogel-encapsulated catalysts are an attractive tool for low-cost intensification of (bio)-processes. Polyvinyl alcohol-sodium alginate hydrogels crosslinked with boric acid and post-cured with sulfate (PVA-SA-BS) have been applied in bioproduction and water treatment processes, but the low pH required for crosslinking may negatively affect biocatalyst functionality. Here, we investigate how crosslinking pH (3, 4, and 5) and time (1, 2, and 8 h) affect the physicochemical, elastic, and process properties of PVA-SA-BS beads. Overall, bead properties were most affected by crosslinking pH. Beads produced at pH 3 and 4 were smaller and contained larger internal cavities, while optical coherence tomography suggested polymer cross-linking density was higher. Optical coherence elastography revealed PVA-SA-BS beads produced at pH 3 and 4 were stiffer than pH 5 beads. Dextran Blue release showed that pH 3-produced beads enabled higher diffusion rates and were more porous. Last, over a 28-day incubation, pH 3 and 4 beads lost more microspheres (as cell proxies) than beads produced at pH 5, while the latter released more polymer material. Overall, this study provides a path forward to tailor PVA-SA-BS hydrogel bead properties towards a broad range of applications, such as chemical, enzymatic, and microbially catalyzed (bio)-processes.
Topics: Polyvinyl Alcohol; Alginates; Hydrogels; Polymers; Hydrogen-Ion Concentration
PubMed: 36460678
DOI: 10.1038/s41598-022-25111-7 -
Journal of Biomedical Materials... Jun 2023Cryogels are support materials which are good at mimicking extracellular matrix due to their excellent hydrophilicity, biocompatibility, and macroporous structure, thus...
Cryogels are support materials which are good at mimicking extracellular matrix due to their excellent hydrophilicity, biocompatibility, and macroporous structure, thus they are useful in facilitating cell activities during healing process. In this study, polyvinyl alcohol-gelatin (PVA-Gel) based cryogel membranes loaded with pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene; PTS) (PVA-Gel/PTS) was synthesized as wound dressing materials. PVA-Gel and PVA-Gel/PTS were synthesized with the polymerization yields of 96% ± 0.23% and 98% ± 0.18%, respectively, and characterized by swelling tests, Brunauer-Emmett-Teller (BET) and scanning electron microscopy (SEM) analysis. The swelling ratios were calculated as 98.6% ± 4.93% and 102% ± 5.1%, macroporosities were determined as 85% ± 2.13% and 88% ± 2.2%, for PVA-Gel and PVA-Gel/PTS, respectively. It was determined that PVA-Gel and PVA-Gel/PTS have 17 m /g ± 0.76 m /g and 20 m /g ± 0.92 m /g surface areas, respectively. SEM studies were demonstrated that they have ~100 μm pore sizes. According to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), trypan blue exclusion and live-dead assay results, it was observed that cell proliferation, cell number and cell viability were higher in PVA-Gel/PTS cryogel at 24, 48, and 72 h compared to PVA-Gel. A strong and transparent fluorescent light intensity was observed indicating higher cell population in PVA-Gel/PTS in comparison with PVA-Gel, according to 4',6-diamidino-2-phenylindole (DAPI) staining. SEM, F-Actin, Giemsa staining and inverted-phase microscope image of fibroblasts in PVA-Gel/PTS cryogels revealed that dense fibroblast proliferation and spindle-shaped morphology of cells were preserved. Moreover, DNA agarose gel data demonstrated that PVA-Gel/PTS cryogels had no effect on DNA integrity. Consequently, produced PVA-Gel/PTS cryogel can be used as wound dressing material to promote wound therapies, inducing cell viability and proliferation.
Topics: Cryogels; Polyvinyl Alcohol; Gelatin; Bandages
PubMed: 36863724
DOI: 10.1002/jbm.b.35230 -
Operative Dentistry Nov 2021To evaluate the three-dimensional (3D) changes of three elastomeric impression materials using a novel measurement method for the first 24 hours after preparation.
OBJECTIVES
To evaluate the three-dimensional (3D) changes of three elastomeric impression materials using a novel measurement method for the first 24 hours after preparation.
METHODS AND MATERIALS
Three impression materials consisting of a low-viscosity polyvinyl siloxane (PVS) (Aquasil LV, Dentsply Sirona, Charlotte, NC, USA) and two vinyl polyether silicone (VPES) materials consisting of a light body (EXA'lence LB, GC America, Alsip, IL, USA) and monophase (EXA'lence Monophase, GC America) materials were used in this study. All materials were prepared following manufacturer's recommendations with approximately 1-2 millimeters of material placed on the measurement pedestal of a calibrated noncontact, video imaging based, volumetric change measuring device (AcuVol ver 2.5.9, Bisco, Schaumburg, IL, USA). Data collection was initiated immediately, with measurements made every 30 seconds for 24 hours. Each material was evaluated 10 times (n=10). Evaluated parameters included were 24-hour mean shrinkage, mean shrinkage at time of recommended first pour, mean shrinkage between recommended first pour and 24 hours, mean maximum shrinkage, and the time of maximum shrinkage. Mean data, both within and between each group, was evaluated using Kruskal-Wallis/Dunn's tests at a 95% level of confidence (α=0.05).
RESULTS
All three materials were found to have significant differences (p<0.001) in volumetric shrinkage over 24 hours. Aquasil LV and EXA'lence LB polymerization shrinkage rates were statistically similar all through the 24-hour evaluation (p=0.92). All three materials demonstrated similar (p=0.19) shrinkage between 10 and 15 minutes after preparation, while between 5 and 16 hours both EXA'lence Monophase and low-viscosity materials demonstrated similar polymerization shrinkage values (p=0.22). EXA'lence Monophase demonstrated significantly greater 24-hour mean shrinkage (p<0.008) as well as shrinkage between recommended first pour time and 24 hours (p=0.003) than Aquasil LV and EXA'lence LB. EXA'lence Monophase demonstrated significantly greater (p=0.002) shrinkage at the recommended time of first pour as compared to Aquasil LV and EXA'lence LB that displayed similar shrinkage (p=0.89). Furthermore, all materials demonstrated increasing polymerization shrinkage values that reached a maximum between 16 for Aquasil LV and 20 hours for EXA'lence LB, after which some relaxation behavior was observed. However, EXA'lence Monophase did not display any relaxation behavior over the 24-hour evaluation.
CONCLUSIONS
Under the conditions of this study, volumetric polymerization shrinkage was observed for one polyvinyl siloxane (PVS) and two vinyl polyether silicone (VPES) materials for up to 24 hours. All impression materials exhibited fast early volumetric shrinkage that continued past the manufacturer's recommended removal time. Dimensional change behavior was not uniform within or between groups; resultant volume change between the manufacturer recommended pouring time and 24 hours might represent up to from 20% to 30% of the total material shrinkage. It may be prudent to pour elastomeric impressions at the earliest time possible following the manufacturer's recommendations.
Topics: Dental Impression Materials; Dental Impression Technique; Materials Testing; Pilot Projects; Polyvinyls; Silicones; Siloxanes; Surface Properties
PubMed: 34919709
DOI: 10.2341/20-265-L -
ACS Biomaterials Science & Engineering May 2024Tissue engineering involves implanting grafts into damaged tissue sites to guide and stimulate the formation of new tissue, which is an important strategy in the field... (Review)
Review
Tissue engineering involves implanting grafts into damaged tissue sites to guide and stimulate the formation of new tissue, which is an important strategy in the field of tissue defect treatment. Scaffolds prepared in vitro meet this requirement and are able to provide a biochemical microenvironment for cell growth, adhesion, and tissue formation. Scaffolds made of piezoelectric materials can apply electrical stimulation to the tissue without an external power source, speeding up the tissue repair process. Among piezoelectric polymers, poly(vinylidene fluoride) (PVDF) and its copolymers have the largest piezoelectric coefficients and are widely used in biomedical fields, including implanted sensors, drug delivery, and tissue repair. This paper provides a comprehensive overview of PVDF and its copolymers and fillers for manufacturing scaffolds as well as the roles in improving piezoelectric output, bioactivity, and mechanical properties. Then, common fabrication methods are outlined such as 3D printing, electrospinning, solvent casting, and phase separation. In addition, the applications and mechanisms of scaffold-based PVDF in tissue engineering are introduced, such as bone, nerve, muscle, skin, and blood vessel. Finally, challenges, perspectives, and strategies of scaffold-based PVDF and its copolymers in the future are discussed.
Topics: Polyvinyls; Tissue Scaffolds; Tissue Engineering; Humans; Printing, Three-Dimensional; Biocompatible Materials; Polymers; Animals; Fluorocarbon Polymers
PubMed: 38621173
DOI: 10.1021/acsbiomaterials.3c01989 -
Materials Science & Engineering. C,... Oct 2019To accomplish a rapid wound healing it is necessary to develop an asymmetric membrane with interconnected pores consisting of a top layer that prevents rapid dehydration...
To accomplish a rapid wound healing it is necessary to develop an asymmetric membrane with interconnected pores consisting of a top layer that prevents rapid dehydration of the wound and bacteria penetration and a sub-layer with high absorption capacity and bactericidal properties. Polycaprolactone (PCL)/polyvinyl acetate (PVAc) asymmetric membranes loaded with the bactericidal monoterpene carvacrol (CRV) were synthesized and characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Mechanical properties in dry and wet conditions and fluid handling behavior were also assessed. In addition, biological studies regarding their bactericidal effects, cytocompatibility and wound closure properties were also developed. Loading efficiencies of 40-50% were achieved in the prepared samples and 85-100% of the loaded CRV was released in simulated wound pH evolution medium. The significant inhibition of Gram negative (Escherichia coli S17) and Gram positive (Staphylococcus aureus ATCC 25923) bacteria growth clearly showed the suitability of the fabricated membranes for wound healing applications. Furthermore, cytocompatibility of the loaded membranes was demonstrated both in 2D and 3D human dermal fibroblast cultures, as well as cell migration was not impaired by released carvacrol from the membranes. These results highlight the potential of these polymeric electrospun membranes for wound healing.
Topics: Anti-Bacterial Agents; Bandages; Cell Movement; Cells, Cultured; Cymenes; Elastic Modulus; Escherichia coli; Fibroblasts; Humans; Hydrogen-Ion Concentration; Materials Testing; Membranes, Artificial; Polyesters; Polyvinyls; Staphylococcus aureus; Wound Healing; Wound Infection
PubMed: 31349490
DOI: 10.1016/j.msec.2019.109822 -
Drug Delivery Dec 2020Amentoflavone (AMF) is a kind of biflavonoids existing in Ginkgo biloba leaves. It has many biological activities, such as antioxidant, anti-inflammatory,...
Amentoflavone (AMF) is a kind of biflavonoids existing in Ginkgo biloba leaves. It has many biological activities, such as antioxidant, anti-inflammatory, anti-bacterial, antiviral, hypoglycemic, anti-tumor and inducing apoptosis. However, its solubility and bioavailability are poor and there are a few studies on it . In this study, to improve its solubility and bioavailability, the nanomicelles were prepared with TPGS and soluplus as carriers for the first time. The particle size, Zeta potential, encapsulation efficiency, drug loading, stability, cytotoxicity, cellular uptake, and metabolites in rats were studied. Cytotoxicity, cellular uptake, and metabolites in rats of AMF-loaded TPGS/soluplus mixed micelles were compared with those of AMF. As a result, AMF-loaded TPGS/soluplus mixed micelles with a particle size of 67.33 ± 2.01 nm and Zeta potential of -0.84133 ± 0.041405 mV were successfully prepared. The encapsulation efficiency and drug loading of the mixed nanomicelles were 99.18 ± 0.76% and 2.47 ± 0.01%, respectively. The physical and chemical properties of the mixed micelles were stable within 60 d, and the cytotoxicity of the mixed micelles was much greater than that of AMF monomers. Thirty-four kinds of metabolites of AMF were identified in rats. The metabolites were mainly distributed in rat feces. No metabolites were detected in bile and plasma. 14 kinds of metabolites of the mixed micelles in rats were detected, including 11 in feces, 6 in urine, and 3 in plasma, which indicated that the bioavailability of AMF has been improved. And the toxicity to cancer cells was enhanced, which laid a foundation for the development of new drugs.
Topics: A549 Cells; Animals; Biflavonoids; Cell Line, Tumor; Cell Survival; Drug Carriers; Drug Stability; Humans; Male; Micelles; Nanoparticles; Particle Size; Polyethylene Glycols; Polyvinyls; Rats; Rats, Sprague-Dawley; Vitamin E
PubMed: 31913733
DOI: 10.1080/10717544.2019.1709920 -
International Journal of Biological... Apr 2023Ionic conductive hydrogels (ICHs) have received widespread attention as an ideal candidate for flexible electronic devices. However, conventional ICHs failed in...
Ionic conductive hydrogels (ICHs) have received widespread attention as an ideal candidate for flexible electronic devices. However, conventional ICHs failed in widespread applications due to their inability to simultaneously possess high toughness, high ionic conductivity, and anti-freezing properties. Here, polyvinyl alcohol (PVA) and polyacrylamide (PAAm) were first dissolved in the zinc chloride solution, in which zinc ions (Zn) act as ionic cross-linkers and conducting ions, followed by the introduction of xanthan gum (XG) with a unique structure of trisaccharide side chains into the PVA/PAAm semi-interpenetrating network to prepare a dual-network ICHs (refers as PPXZ). Enabled by the synergistic effect of intermolecular chemical covalent cross-linking and physical cross-linking, PPXZ hydrogels exhibit significantly improved mechanical properties without sacrificing electrical conductivity. Furthermore, PPXZ hydrogels are successfully applied to flexible electronic devices, such as strain sensors and zinc ion hybrid supercapacitors, exhibiting satisfactory sensing sensitivity and cycling stability at a wide temperature range, respectively. Even at a high current density (10 A g), the capacity of the supercapacitor retains 88.24 % after 10,000 cycles. This strategy provides new insight for ICHs in wide temperature-applied flexible electronic devices.
Topics: Polyvinyl Alcohol; Electric Conductivity; Electronics; Hydrogels; Ions
PubMed: 36754269
DOI: 10.1016/j.ijbiomac.2023.123573 -
Macromolecular Bioscience Nov 2022Preventing bacterial infection and controlling the inflammatory response occupy important positions in wound treatment. Although loading wound dressings with...
Preventing bacterial infection and controlling the inflammatory response occupy important positions in wound treatment. Although loading wound dressings with antibacterial or anti-inflammatory drugs/molecules is an effective approach to address these issues, simultaneous sustained release of these drugs remains challenging. Herein, hydrophilic polyhexamethylene guanidine hydrochloride (PHGC) and hydrophobic indomethacin (Indo) are loaded in hydrophilic polyvinyl alcohol (PVA) and hydrophobic polycaprolactone (PCL) nanofibers respectively by bidirectional electrospinning to form an antibacterial and anti-inflammatory PCL-Indo/PVA-PHGC wound dressing. The fabricated nanofiber membrane exhibits 100% disinfection activity to both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria because of the release of the broad-spectrum antibacterial molecule PHGC. Additionally, the loading of Indo in the nanofiber membrane enhances the expression level of IL-10, while inhibiting those of IL-6 and TNF-α in the RAW264.7 mouse cells. In the interwoven membrane of PCL and PVA fibers, the release of hydrophobic Indo is hindered by hydrophilic PHGC and PVA fibers, and similarly, the release of hydrophilic PHGC is hindered by hydrophobic Indo and PCL fibers. In conclusion, the PCL-Indo/PVA-PHGC nanofiber membrane has excellent antibacterial, anti-inflammatory, and sustained-release effects, and thus regulates the immune microenvironment of the cells to potentially promote wound healing.
Topics: Mice; Animals; Nanofibers; Staphylococcus aureus; Escherichia coli; Drug Liberation; Anti-Bacterial Agents; Polyvinyl Alcohol; Anti-Inflammatory Agents
PubMed: 35856465
DOI: 10.1002/mabi.202200150 -
Chemistry (Weinheim An Der Bergstrasse,... Mar 2023There is an endogenous electric field in living organisms, which plays a vital role in the development and regeneration of bone tissue. Therefore, self-powered...
There is an endogenous electric field in living organisms, which plays a vital role in the development and regeneration of bone tissue. Therefore, self-powered piezoelectric material for bone repair has become hot research in recent years. However, the current piezoelectric materials for tissue regeneration still have the shortcomings of lack of biological activity and three-dimensional structure. Here, we proposed a three-dimensional polyurethane foam (PUF) scaffold coated with piezoelectric poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and modified by a calcium phosphate (CaP) mineralized coating. The preferred scaffold has an open circuit voltage and short circuit current output of 5 V and 200 nA. Combining the physical and chemical properties of the CaP coating, the piezoelectric signal of PVDF-HFP and the three-dimensional structure of PUF, the scaffold exhibits superior promotion of cell osteogenic differentiation and ectopic bone formation in vivo. The mechanism is attributed to an increase in intracellular Ca levels in response to chemical and piezoelectric stimulation with the material. This research not only paves the way for the application of piezoelectric scaffolds to stimulate osteoblasts differentiation in situ, but also lays the foundation for the clinical treatment of long-term osteoporosis.
Topics: Polyvinyls; Cell Differentiation; Tissue Scaffolds; Osteogenesis
PubMed: 36478479
DOI: 10.1002/chem.202203166