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International Journal of Molecular... Jan 2023As an energy storage technology, supercapacitors (SCs) have become an important part of many electronic systems because of their high-power density, long cycle life, and...
As an energy storage technology, supercapacitors (SCs) have become an important part of many electronic systems because of their high-power density, long cycle life, and maintenance-free characteristics. However, the widespread development and use of electronics, including SCs, have led to the generation of a large amount of e-waste. In addition, achieving compatibility between stability and biodegradability has been a prominent challenge for implantable electronics. Therefore, environmentally friendly SCs based on polypyrrole (PPy)-stabilized polypeptide (FF) are demonstrated in this study. The fully degradable SC has a layer-by-layer structure, including polylactic acid/chitosan (PLA-C) support layers, current collectors (Mg), FF/PPy composite layers, and a polyvinyl alcohol/phosphate buffer solution (PVA/PBS) hydrogel. It has the advantages of being light, thin, flexible, and biocompatible. After 5000 cycles in air, the capacitance retention remains at up to 94.7%. The device could stably operate for 7 days in a liquid environment and completely degrade in vitro within 90 days without any adverse effect on the environment. This work has important implications for eco-friendly electronics and will have a significant impact on the implantable biomedical electronics.
Topics: Polymers; Pyrroles; Polyvinyl Alcohol; Peptides
PubMed: 36768819
DOI: 10.3390/ijms24032497 -
The Journal of Extra-corporeal... Jun 2020The U.S. healthcare system generates more than five billion pounds of waste each year. Waste disposal has become a serious environmental problem facing healthcare... (Review)
Review
The U.S. healthcare system generates more than five billion pounds of waste each year. Waste disposal has become a serious environmental problem facing healthcare institutions. The operating room is the second largest source of hospital waste, and no current standards exist regarding perfusion waste reuse or recycling. A typical perfusion circuit produces approximately 15 pounds of plastic that ends up incinerated once used. Contaminated perfusion circuits consisting primarily of polyvinyl chloride (PVC) and polycarbonate are difficult to sterilize, reuse, or recycle. A literature review of Internet-based and peer-reviewed publications was conducted to identify all resources that describe sterilizing, dechlorinating, reusing, and recycling of medical-grade disposable products. There are several chemical methods available to re-harvest PVC after it has been properly decontaminated and melted down. Dichlorination by near-critical methanol shows promise in the recovery of additives such as plasticizers, stabilizers, and lubricants. The reinjection of PVC may have ecological and economic advantages. Dechlorinated PVC also creates a less toxic by-product when incinerated. Although this process is not recycling, it lessens the impact of poisonous chlorine gas release into the atmosphere. Sterilizing, dechlorinating, and recycling the perfusion circuit may be a promising avenue for reducing the ecological impact of perfusion waste. Although an economically sensitive mode of reusing, reducing, and recycling a circuit does not currently exist, this presentation will explore the perfusion waste dilemma and present potential solutions in hopes of promoting future reuse and recycling opportunities.
Topics: Medical Waste; Polyvinyl Chloride; Recycling; Refuse Disposal
PubMed: 32669740
DOI: 10.1182/ject-1900023 -
Polimery W Medycynie 2022As the number of new drug candidates that are poorly soluble in water grows, new technologies that enable the enhancement of their solubility are needed. This is the... (Review)
Review
As the number of new drug candidates that are poorly soluble in water grows, new technologies that enable the enhancement of their solubility are needed. This is the case with amorphous solid dispersions (ASDs) that, nowadays, not only ensure the solubility, but can also be used to control the release rate of poorly soluble drugs. However, this dosage form must overcome the major disadvantage of ASDs, which is limited stability upon storage. Thus, a thorough knowledge on polymeric carriers that can enhance drug solubility while ensuring stability in the amorphous form is necessary. In this review, the state of the art in the application of Kollidon® VA 64 (copovidone) and Soluplus® (graft copolymer of polyvinyl caprolactam-polyvinyl acetate and poly(ethylene glycol) (PEG)) in the manufacturing of ASDs over the last 20 years is presented. Apart from the classical methods, namely solvent evaporation or melting, more advanced technologies such as pulse combustion drying, high-speed electrospinning and single-step 3D printing are described. It has been shown that both the dissolution rate (in vitro) and enhancement in bioavailability (in vivo) regarding poorly soluble active ingredients of natural or synthetic origin are possible using these matrix-forming polymers.
Topics: Chemistry, Pharmaceutical; Drug Compounding; Polyethylene Glycols; Polymers; Polyvinyls; Povidone; Solubility
PubMed: 35766434
DOI: 10.17219/pim/150267 -
Australian Dental Journal Dec 1999
Topics: Colloids; Dental Impression Materials; Elastomers; Humans; Polyvinyls; Surface Properties; Water; Wettability
PubMed: 10687241
DOI: No ID Found -
Korean Journal of Anesthesiology Aug 2023Direct insertion of a double-lumen tube (DLT) using a flexible fiberoptic bronchoscope (FOB) is an option for DLT intubation. The difficult process of fiberoptic...
BACKGROUND
Direct insertion of a double-lumen tube (DLT) using a flexible fiberoptic bronchoscope (FOB) is an option for DLT intubation. The difficult process of fiberoptic intubation is that the different properties of polyvinyl chloride and silicone DLTs may affect railroading differently. Therefore, we aimed to compare intubation using polyvinyl chloride and silicone DLTs over an FOB.
METHODS
Patients aged 19-75 years who required one-lung ventilation under general anesthesia were enrolled in this study. After induction of anesthesia, the anesthesiologist intubated the DLT using FOB. The primary outcome was the difficulty of railroading over the flexible FOB scaled into five grades (I, II-1, II-2, III, and IV). Additionally, the intubation time and mucosal damage were recorded.
RESULTS
A total of 46 patients participated in this study, 23 each in the silicone and polyvinyl groups. The difficulty of railroading over the FOB was significantly different between the two groups (P < 0.001). In the silicone group, the grades of difficulty in railroading were limited to I and II-1; 20 patients (87%) presented no difficulty in advancing the tube. In contrast, in the polyvinyl group, 13 patients (57%) had scores of II-2 and III. Both the intubation time and mucosal damage were significantly better in the silicone group than in the polyvinyl group.
CONCLUSIONS
Intubation using a silicone DLT over an FOB was easier and faster than that with a polyvinyl chloride DLT with lesser trauma around the glottis.
Topics: Humans; Bronchoscopes; Polyvinyl Chloride; Intubation, Intratracheal; Polyvinyls; Silicones; Anesthesia, General
PubMed: 36577506
DOI: 10.4097/kja.22649 -
Translational Vision Science &... Apr 2020This study compared intraocular toxicity of intravitreally injected povidone-iodine (PI) and polyvinyl alcohol-iodine (PAI) in rabbits.
PURPOSE
This study compared intraocular toxicity of intravitreally injected povidone-iodine (PI) and polyvinyl alcohol-iodine (PAI) in rabbits.
METHODS
In each rabbit, 0.1 mL of PI or PAI solution was injected intravitreally into one eye and saline was injected into the other. PI was tested at available iodine concentrations of 0.05%, 0.1%, 0.2%, and 0.5%, and PAI at 0.05%, 0.1%, and 0.2% (n = 6 each). Electroretinograms were recorded before injection and 1, 7, and 14 days after injection. Pathological examinations of eyeballs were performed on day 15.
RESULTS
Mean b-/a-wave ratios of the electroretinograms did not change in eyes injected with 0.05%, 0.1%, or 0.2% PI (PI-0.05, PI-0.1, and PI-0.2, respectively) or in eyes injected with 0.05% or 0.1% PAI (PAI-0.05 and PAI-0.1, respectively) compared to saline-injected eyes, but was transiently impaired on day 1 in PAI-0.2 eyes. Histopathologically, no retinal abnormalities were observed in PI-0.05, PAI-0.05, or PAI-0.1 eyes. One PI-0.1 eye first showed localized inflammatory cell infiltration in the inferior retinal region. Two PI-0.2 eyes and one PAI-0.2 eye had retinal degeneration and inflammatory cell infiltration. In the PI-0.5 group, extensive inflammatory cell infiltration was observed in six eyes and inferior retinal detachment in five eyes.
CONCLUSIONS
PI and PAI have equivalent retinal toxicity profiles, and retinal toxicity first affects the inner retinal layer in the inferior region. The highest non-retinotoxic vitreous concentration is 0.0033% available iodine from intravitreal injection of PI or PAI containing 0.05% available iodine.
TRANSLATIONAL RELEVANCE
Low concentrations of PI or PAI can be used to wash the ocular surface during surgery or intravitreal injection to prevent endophthalmitis.
Topics: Animals; Intravitreal Injections; Iodine; Polyvinyl Alcohol; Povidone-Iodine; Rabbits; Vitreous Body
PubMed: 32821477
DOI: 10.1167/tvst.9.5.5 -
Biomedicine & Pharmacotherapy =... Nov 2022Microwave is commonly used in the life, manufacturing and military fields, which may induce body injuries. Brain is the major target organ of microwave radiation and...
Microwave is commonly used in the life, manufacturing and military fields, which may induce body injuries. Brain is the major target organ of microwave radiation and microwave-induced brain injury (MIBI) can lead to insomnia, dreaminess, and a decline in learning and memory. However, there is no clinical medications are available currently. Calcium channel blockers may protect the brain tissue from microwave but most of them cannot enter the brain. Here, we selected a calcium channel blocker-cinnarizine to prepare its dissolving microneedles (MNs) for the therapy of MIBI. The cinnarizine MNs was composed of polyvinyl pyrrolidone (PVP) K90 as the tip, the photopolymerized PVP as the base and the drug, which owned high mechanical strength, leading to easily piecing the skin on the neck and high drug release in vivo. The cinnarizine MNs markedly improved the recovery of spatial memory and spontaneous exploratory behavior of the rats after microwave radiation by inhibiting the expression of calcineurin and calpain-1. The dissolving MN technique is a promising method to improve drugs into the body and perform the anti-microwave radiation action.
Topics: Rats; Animals; Administration, Cutaneous; Cinnarizine; Calcium Channel Blockers; Needles; Drug Delivery Systems; Calcineurin; Calpain; Polyvinyls; Povidone; Brain Injuries
PubMed: 36271560
DOI: 10.1016/j.biopha.2022.113779 -
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 -
Radiology. Imaging Cancer Jul 2022
Topics: Embolization, Therapeutic; Polyvinyls; Vascular Surgical Procedures
PubMed: 35838533
DOI: 10.1148/rycan.229012 -
Protein & Cell Sep 2012The low abundance and highly hydrophobic nature of most membrane proteins make their analysis more difficult than that for common soluble proteins. Successful membrane... (Review)
Review
The low abundance and highly hydrophobic nature of most membrane proteins make their analysis more difficult than that for common soluble proteins. Successful membrane protein identification is largely dependent on the sample preparation including the enrichment and dissolution of the membrane proteins. A series of conventional and newly developed methods has been applied to the enrichment of low-abundance membrane proteins at membrane and/or protein levels and to the dissolution of hydrophobic membrane proteins. However, all the existing methods have inherent advantages and limitations. Up to now, there has been no unique method that can universally be employed to solve all the problems and more efforts are needed in improving sample preparation for the analysis of membrane proteomes.
Topics: Chromatography, High Pressure Liquid; Mass Spectrometry; Membrane Proteins; Membranes, Artificial; Oxidation-Reduction; Polyvinyls; Proteome; Proteomics
PubMed: 22926766
DOI: 10.1007/s13238-012-2062-1