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Molecular Pharmaceutics Jan 2021We present a new approach for characterizing drug-polymer interactions in aqueous media, using sedimentation velocity analytical ultracentrifugation (AUC). We...
We present a new approach for characterizing drug-polymer interactions in aqueous media, using sedimentation velocity analytical ultracentrifugation (AUC). We investigated the potential interaction of ketoconazole (KTZ), a poorly water-soluble drug, with polyacrylic acid (PAA) and a polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus) in aqueous buffers. The effect of the polymer on the sedimentation coefficient of the drug was the observable metric. The drug alone, when subjected to AUC, exhibited a very narrow sedimentation peak at 0.2 Svedberg (S), in agreement with the expectation for a monomeric drug with a molar mass < 1000 Dalton. Conversely, the neat polymers showed broad profiles with higher sedimentation coefficients, reflecting their larger more heterogeneous size distributions. The sedimentation profiles of the drug-polymer mixtures were expectedly different from the profile of the neat drug. With KTZ-Soluplus, a complete shift to faster sedimentation times (indicative of an interaction) was observed, while with KTZ-PAA, a split peak indicated the existence of the drug in both free and interacting states. The sedimentation profile of carbamazepine, a second model drug, in the presence of hydroxypropyl methyl cellulose acetate succinate (HPMCAS, another polymer) revealed multiple "populations" of drug-polymer species, very similar to the sedimentation profile of neat HPMCAS. The interactions probed by AUC were compared with the results from isothermal titration calorimetry. In vitro dissolution tests performed on amorphous solid dispersions prepared with the same drug-polymer pairs suggested that the interactions may play a role in prolonging drug supersaturation. The results show the possibility of characterizing drug-polymer interactions in aqueous solution with high hydrodynamic resolution, addressing a major challenge frequently encountered in the mechanistic investigations of the dissolution behavior of amorphous solid dispersions.
Topics: Acrylic Resins; Crystallization; Ketoconazole; Methylcellulose; Pharmaceutical Preparations; Polyethylene Glycols; Polymers; Polyvinyls; Solubility; Ultracentrifugation; Water; X-Ray Diffraction
PubMed: 33264020
DOI: 10.1021/acs.molpharmaceut.0c00849 -
Journal of Biomedical Materials... May 2023This work aimed the development and evaluation of the wound healing activity of films based on sodium alginate, polyvinyl alcohol (PVA) and Ca loaded with Agaricus...
This work aimed the development and evaluation of the wound healing activity of films based on sodium alginate, polyvinyl alcohol (PVA) and Ca loaded with Agaricus blazei Murill hydroalcoholic extract (AbE). Firstly, AbE was prepared using a previously standardized methodology. The films were prepared by casting technique and cross-linked with Ca using CaCl as cross-linking agent. The physicochemical, morphological and water vapor barrier properties of the films were analyzed and the pre-clinical efficacy was investigated against the cutaneous wound model in mice. The films showed barrier properties to water vapor promising for wound healing. AbE showed physical and chemical interactions between both polymers, noticed by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and thermal analysis. The delivery of AbE in alginate/PVA films enhanced the antioxidant and wound healing properties of these polymers. Consequently, a reduction of malondialdehyde levels was observed, as well as an increase of the epidermis/dermis thickness and enhancement in collagen I deposition. Thus, these formulations are promising biomaterials for wound care and tissue repairing.
Topics: Mice; Animals; Alginates; Polyvinyl Alcohol; Steam; Wound Healing
PubMed: 36455230
DOI: 10.1002/jbm.b.35212 -
Environmental Science & Technology Oct 2021Phthalic acid esters (PAEs) are the most common plasticizers, approximately 90% of which are used in polyvinyl chloride (PVC) products, but they are also endocrine...
Phthalic acid esters (PAEs) are the most common plasticizers, approximately 90% of which are used in polyvinyl chloride (PVC) products, but they are also endocrine disruptors that have attracted considerable attention. The metabolism of PAEs in PVC products in China from 1958 to 2019 was studied using dynamic material flow analysis. The results showed that the total consumption of PAEs was 29.2 Mt in the past 60 years. By 2019, the in-use stocks of PAEs were 5.0 Mt. Construction materials were always in the leading position with respect to the consumption and in-use stocks of PAEs. A total PAE loss of 22.7 Mt was generated, of which 68.0% remained in waste distributed in landfills (50.1%), storage sites (5.5%), the environment (44.4%), 12.4% was eliminated during waste incineration and open burning, and 19.6% was emitted into the environment. From 1958 to 2019, 496.4, 55.6, and 3905.0 kt of PAEs were emitted into water, air, and soil, respectively. The use and waste treatment stages contributed 79.3 and 19.9% of the emissions of PAEs in the life cycle, respectively. This study systematically analyzed the metabolism of PAEs at the national level over a long-time span, providing useful information on the life cycle management of PAEs.
Topics: China; Esters; Phthalic Acids; Polyvinyl Chloride
PubMed: 34617437
DOI: 10.1021/acs.est.1c02374 -
The Journal of Pharmacy and Pharmacology Jun 2021Current treatment for autonomic dysreflexia (AD) involves rupturing a liquid-filled soft capsule of nifedipine to aid rapid drug release and absorption, however, this...
OBJECTIVES
Current treatment for autonomic dysreflexia (AD) involves rupturing a liquid-filled soft capsule of nifedipine to aid rapid drug release and absorption, however, this application is not covered under the manufacturer's license. The objective of the current work was to design a rapidly dissolving solid dosage formulation for the treatment of AD as an alternative to the off-license "bite and swallow" use of currently available commercial products.
METHODS
Amorphous solid dispersions (ASDs) of nifedipine were prepared by spray-drying using three different polymers: hydroxypropyl methyl cellulose (HPMC), polyvinyl pyrrolidone (PVP) and polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol (Soluplus), at a 15% w/w drug loading and were formulated and compressed into tablets. Dissolution testing was performed in the paddle dissolution apparatus using either a monophasic or biphasic medium.
KEY FINDINGS
The PVP-nifedipine ASD tablets exhibited rapid dissolution, with 35% of the total nifedipine dose dissolving within 15 min in the monophasic dissolution medium. The HPMC-nifedipine ASD exhibited a very slow dissolution, while the Solupus-nifedipine system exhibited no nifedipine release over 120 min. When tested in the biphasic dissolution medium, the PVP-nifedipine ASD tablets exhibited a release profile comparable to that of the pre-split/ruptured nifedipine soft capsule product.
CONCLUSIONS
This study demonstrates that a nifedipine-PVP ASD is a promising formulation strategy in the treatment of AD.
Topics: Autonomic Dysreflexia; Calcium Channel Blockers; Chemistry Techniques, Synthetic; Drug Compounding; Drug Liberation; Excipients; Humans; Hypromellose Derivatives; Nifedipine; Polyethylene Glycols; Polyvinyls; Pyrrolidines; Solubility; Spray Drying
PubMed: 33749786
DOI: 10.1093/jpp/rgab034 -
International Journal of Biological... Dec 2023Membrane separation is considered an effective approach to water purification. Nevertheless, membrane fouling dramatically decreases the separation efficiency and...
Super-wetting and self-cleaning polyvinyl alcohol/sodium alginate nanofiber membrane decorated with MIL-88A(Fe) for efficient oil/water emulsion separation and dye degradation.
Membrane separation is considered an effective approach to water purification. Nevertheless, membrane fouling dramatically decreases the separation efficiency and lifetime of membranes, thus limiting its further development and application. Herein, a multifunctional self-cleaning MIL-88A(Fe) decorated polyvinyl alcohol/sodium alginate (MIL-88A(Fe)@PVA-SA) nanofiber membrane was prepared by electrospinning and in-situ growth methods for the separation of oil/water emulsions and photo-Fenton degradation of dyes. The membrane possesses superhydrophilicity with a water contact angle (WCA) of 0° and superoleophobicity with underwater oil contact angle (UCA) of 161.7°, and exhibits superior separation efficiency (>99.5 %) and permeation flux (1140-2455 L/m/h) for different oil/water emulsions. Moreover, the membrane exhibited an outstanding photo-Fenton performance under visible light, with degradation efficiencies (~99.9 %) towards methylene blue (MB) and reactive red 24 (RR24) within 90 min. Importantly, the membrane can be easily regenerated by simple rinsing and photo-Fenton self-cleaning treatment. In this study, MIL-88A(Fe)@PVA-SA nanofiber membrane has a promising application in dye removal and oil/water separation, providing a new idea to develop novel membrane materials.
Topics: Emulsions; Nanofibers; Polyvinyl Alcohol; Alginates; Coloring Agents
PubMed: 37804898
DOI: 10.1016/j.ijbiomac.2023.127205 -
Journal of Colloid and Interface Science Nov 2022In this study, polyvinyl pyrrolidone modified tungsten disulfide (WS-PVP) nanoflower was synthesized using a simple and effective one-pot method. Owing to the surface...
In this study, polyvinyl pyrrolidone modified tungsten disulfide (WS-PVP) nanoflower was synthesized using a simple and effective one-pot method. Owing to the surface polyvinyl pyrrolidone (PVP) modification, WS-PVP nanoflowers showed excellent colloidal stability in different circumstances, which can be well dispersed in water, saline, and cell culture medium. Meanwhile, the WS-PVP nanoflowers have a good biocompatibility both in vitro and in vivo. Further studies confirmed that the WS-PVP nanoflowers have the ability of simulating catalase, superoxide dismutase and glutathione peroxidase enzymes and scavenging reactive oxygen species (ROS). Therefore, WS-PVP nanoflowers were used to treat reactive oxygen species-related diseases, which showed the cell protection effect and significantly improved the treatment results of acute liver injury on mice. We hope that our findings will facilitate the development of nanomaterials with multiple enzymatic mimicking properties and further clinical application of tungsten-based ROS scavengers in biomedical therapy and research.
Topics: Animals; Liver; Mice; Polyvinyls; Povidone; Reactive Oxygen Species; Sulfides; Tungsten Compounds
PubMed: 35749849
DOI: 10.1016/j.jcis.2022.06.043 -
Biomaterials Advances Aug 2022A composite microneedle patch (MN patch) is developed for oral transmucosal administration. To improve the oral transmucosal drug delivery efficiency, the composite MN...
A composite microneedle patch (MN patch) is developed for oral transmucosal administration. To improve the oral transmucosal drug delivery efficiency, the composite MN patch is designed to consist of an array of 100 dissolvable microneedles (MNs) with drug-loaded tips and a backing layer. The MNs are composed of two parts, the hyaluronic acid (HA) tip part and the polyvinylpyrrolidone (PVP) base part. Due to the small size and sufficient mechanical strength, the HA-PVP MNs can painlessly penetrate the oral mucosa barrier and deliver drugs directly to the basal layer or submucosa. Betamethasone sodium phosphate (BSP), as the model drug, is concentrated in the HA tip parts to avoid the drug waste caused by mucosa elasticity. Considering the special moist environment and saliva flow in the mouth, a double-layer backing layer composed of a poly(vinyl alcohol) (PVA) adhesive layer and an ethyl cellulose (EC) waterproof layer is designed and constructed, which could reduce the saliva flow effects. The in vitro and in vivo results demonstrate that the MN patch could achieve rapid and efficient BSP release in oral mucosa due to the rapid dissolution of HA. The proposed MN patch provides a novel strategy for the therapy of oral mucosal diseases.
Topics: Drug Delivery Systems; Hyaluronic Acid; Polyvinyl Alcohol
PubMed: 35882148
DOI: 10.1016/j.bioadv.2022.213001 -
Chemosphere Nov 2022Microalgae cultivation in open ponds requires a large footprint, while most photobioreactors need improvement in the ratio of surface to volume and energy consumption....
Microalgae cultivation in open ponds requires a large footprint, while most photobioreactors need improvement in the ratio of surface to volume and energy consumption. In this study, polyethersulfone (PES) and poly(vinylidene fluoride) (PVDF) hollow fiber membranes with a large surface area were rearranged into open-ended and dead-ended configurations to improve the air-liquid interface cultivation of Navicula incerta. N. incerta were successfully grown on the porous membrane surface with the nutrients circulating inside the lumen. Fourier-transform infrared spectra showed the accumulation of polysaccharides, proteins and humic acids. Hydrophilic polysaccharides reduced water contact angles on PES and PVDF membranes to 37.2 ± 2.6° and 55.7 ± 3.3°, respectively. However, the porosity of PES (80.1 ± 1.1%) and PVDF (61.3 ± 4.5%) membranes were not significantly affected even after cultivation and harvesting of N. incerta. Scanning electron images further confirmed that N. incerta, cell debris and extracellular organic matter accumulated on the membrane. With large pores and a hydrophobic surface, PVDF hollow fiber membranes offered a greater improvement in N. incerta cell growth rate compared to PES hollow fiber membranes despite using different configurations. In the dead-ended configuration, they even attained the greatest improvement in N. incerta growth rate, up to 54.0%. However, PES hollow fiber membranes only achieved improvement in harvesting efficiency within the range of 18.7-38.0% due to weak cell adhesion. PVDF hollow fiber membranes significantly promoted the growth of microalgae N. incerta through the air-liquid interface system, leading to potential applications in wastewater treatment.
Topics: Fluorocarbon Polymers; Humic Substances; Membranes, Artificial; Polymers; Polyvinyls; Sulfones; Water
PubMed: 35820481
DOI: 10.1016/j.chemosphere.2022.135625 -
International Journal of Biological... Jun 2023Due to their large specific surface area and numerous diffusion channels, hollow fibers are widely used in wastewater treatment. In this study, we successfully...
Due to their large specific surface area and numerous diffusion channels, hollow fibers are widely used in wastewater treatment. In this study, we successfully synthesized a chitosan (CS)/polyvinylpyrrolidone (PVP)/polyvinyl alcohol (PVA) hollow nanofiber membrane (CS/PVP/PVA-HNM) via coaxial electrospinning. This membrane demonstrated remarkable permeability and adsorption separation. Specifically, the CS/PVP/PVA-HNM had a pure water permeability of 4367.02 L·m·h·bar. The hollow electrospun nanofibrous membrane exhibited a continuous interlaced nanofibrous framework structure with the extraordinary advantages of high porosity and high permeability. The rejection ratios of CS/PVP/PVA-HNM for Cu, Ni, Cd, Pb, malachite green (MG), methylene blue (MB) and crystal violet (CV) were 96.91 %, 95.29 %, 87.50 %, 85.13 %, 88.21 %, 83.91 % and 71.99 %, and the maximum adsorption capacities were 106.72, 97.46, 88.10, 87.81, 53.45, 41.43, and 30.97 mg·g, respectively. This work demonstrates a strategy for the synthesis of hollow nanofibers, which provides a novel concept for the design and fabrication of highly efficient adsorption and separation membranes.
Topics: Chitosan; Nanofibers; Polyvinyl Alcohol; Povidone; Metals, Heavy; Coloring Agents
PubMed: 37003384
DOI: 10.1016/j.ijbiomac.2023.124264 -
Bio-medical Materials and Engineering 2020The design and fabrication of hemocompatible and low-toxicity formulations remains a challenging task. Hydrogels are of considerable importance for biomedical...
BACKGROUND
The design and fabrication of hemocompatible and low-toxicity formulations remains a challenging task. Hydrogels are of considerable importance for biomedical applications since they are highly compatible with living tissue, both in vivo and in vitro.
OBJECTIVE
The present study aimed to develop and evaluate the characterizations and in vitro hemocompatibility of a hydrogel using polyvinyl alcohol and gelatin with different concentrations.
METHODS
The gelling process was realized by cross-linking the polyvinyl alcohol and gelatin. The morphological and structural examinations of the synthetic hydrogels were done by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The swelling behavior of the prepared hydrogels in water was evaluated. Prothrombin time, activated partial thromboplastin time, and thrombin time were measured, and a hemolysis test was done to evaluate the hemocompatibility of prepared hydrogels.
RESULTS
The increase of the gelatin concentration in polyvinyl gelatin hydrogel increases the porosity and enhances the absorptivity of the prepared hydrogel. The measured hematological parameters indicated enhancement of hemocompatibility as the gelatin concentration was increased in the prepared hydrogel.
CONCLUSIONS
The results obtained from this study confirm that gelatin was able to improve the properties of the polyvinyl alcohol-gelatin hydrogel and enhance the hemocompatibility. Thus, the prepared hydrogel could be used in a variety of biomedical applications.
Topics: Gelatin; Hydrogels; Polyvinyl Alcohol; Porosity; Water
PubMed: 32716341
DOI: 10.3233/BME-201096