Oxidation–Responsive Emulsions Stabilized with Poly(Vinyl Pyrrolidone-co-allyl Phenyl Sulfide)

Oxidation-responsive emulsions were obtained by stabilizing mineral oil droplets using amphiphilic poly(vinyl pyrrolidone-co-allyl phenyl sulfide) (P(VP-APS)). 1H nuclear magnetic resonance (NMR) spectroscopy revealed that P(VP-APS) whose APS content was 0%, 3.28%, 3.43% and 4.58% were successfully prepared by free radical reaction and the sulfide of APS was oxidized by H2O2 treatment. X-ray Photoelectron Spectroscopy (XPS) also disclosed that the sulfide of APS was oxidized to sulfone by the oxidizing agent. The optical density of copolymer solutions and the interfacial activity of the copolymers markedly decreased by H2O2 treatment possibly because the sulfide of APS was oxidized and the amphiphilicity of the copolymers were weakened. The increase rate of the oil droplet diameter of the emulsions was outstandingly promoted when H2O2 solution (10%, v/v) was used as an aqueous phase. The phase separation of the emulsions was also expedited by the oxidizing agent. The oxidation of APS and the weakened interfacial activity were thought to be a main reason for the demulsification of P(VP-APS)-stabilized emulsions.

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Preparation of PCL/PVP/Ag Nanofiber Membranes by Electrospinning Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.580 ◽

2012 ◽

Vol 268-270 ◽

pp. 580-583 ◽

Cited By ~ 3

Author(s):

Yong Tang Jia ◽

Cui Wu ◽

Feng Chun Dong ◽

Gang Huang ◽

Xian Hua Zeng

Keyword(s):

Silver Nanoparticles ◽

Photoelectron Spectroscopy ◽

Composite Nanofibers ◽

Average Diameter ◽

Vinyl Pyrrolidone ◽

X Ray Diffraction ◽

X Ray ◽

Electrospinning Method ◽

Nanofiber Membranes ◽

Poly Vinyl Pyrrolidone

The composite nanofiber membranes of poly (ε-caprolactone)/poly(vinyl pyrrolidone) (PCL/PVP) containing silver nanoparticles were prepared by electrospinning method. The morphology of composite nanofibers was characterized by scanning electron microscopy (SEM). The silver nanoparticles on the electrospun fibers were characterized by X-Ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The contact angle and water uptake of PCL/PVP/Ag nanofiber membranes were measured. The SEM photos indicated that the average diameter of the fibers was significantly decreased with the addition of silver nanoparticles. The X-Ray images showed that Ag nanoparticles were distributed on the surface of nanofiber membranes. When the PVP mole ratio was higher than 15%, the nanofiber membranes showed good hydrophilic property. The PCL/PVP/Ag nanofiber membranes could be applied to prepare wound dressing.

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Benzoyl peroxide as a novel oxidizing agent in a polyaniline dispersion: Synthesis and characterization of a pure polyaniline–poly(vinyl pyrrolidone) composite

Journal of Applied Polymer Science ◽

10.1002/app.27589 ◽

2008 ◽

Vol 108 (2) ◽

pp. 825-832 ◽

Cited By ~ 16

Author(s):

S. Palaniappan ◽

M. Sairam

Keyword(s):

Benzoyl Peroxide ◽

Vinyl Pyrrolidone ◽

Synthesis And Characterization ◽

Oxidizing Agent ◽

Poly Vinyl Pyrrolidone

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The Structure of Radiation Cross-Linked Poly (ethylene oxide) Gels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064438 ◽

1971 ◽

Vol 29 ◽

pp. 76-77

Author(s):

C. E. Cluthe ◽

G. G. Cocks

Keyword(s):

Molecular Weight ◽

Ethylene Oxide ◽

Parallel Plate ◽

Average Molecular Weight ◽

Radical Reaction ◽

Free Radical Reaction ◽

Nitrogen Gas ◽

Poly Ethylene Oxide ◽

Poly Ethylene ◽

Initial Viscosity

Aqueous solutions of a 1 weight-per cent poly (ethylene oxide) (PEO) were degassed under vacuum, transferred to a parallel plate viscometer under a nitrogen gas blanket, and exposed to Co60 gamma radiation. The Co60 source was rated at 4000 curies, and the dose ratewas 3.8x105 rads/hr. The poly (ethylene oxide) employed in the irradiations had an initial viscosity average molecular weight of 2.1 x 106.The solutions were gelled by a free radical reaction with dosages ranging from 5x104 rads to 4.8x106 rads.

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Hydrogen bonding interactions and miscibility studies of poly(amide)/poly(vinyl pyrrolidone) blends containing mangiferin

Polymer ◽

10.1016/j.polymer.2009.04.054 ◽

2009 ◽

Vol 50 (13) ◽

pp. 2885-2892 ◽

Cited By ~ 16

Author(s):

Chandrasekaran Neelakandan ◽

Thein Kyu

Keyword(s):

Hydrogen Bonding ◽

Vinyl Pyrrolidone ◽

Hydrogen Bonding Interactions ◽

Poly Vinyl Pyrrolidone ◽

Miscibility Studies

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Relating the dynamics of hydrated poly(vinyl pyrrolidone) to the dynamics of highly asymmetric mixtures and polymer blends

Journal of Molecular Liquids ◽

10.1016/j.molliq.2021.115907 ◽

2021 ◽

pp. 115907

Author(s):

Kaito Sasaki ◽

Masanobu Takatsuka ◽

Naoki Shinyashiki ◽

Kia L. Ngai

Keyword(s):

Polymer Blends ◽

Vinyl Pyrrolidone ◽

Poly Vinyl Pyrrolidone

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ALD coating of centrifugally spun polymeric fibers and postannealing: case study for nanotubular TiO2 photocatalyst

Nanoscale Advances ◽

10.1039/d1na00288k ◽

2021 ◽

Author(s):

Martina Rihova ◽

Oksana Yurkevich ◽

Martin Motola ◽

Ludek Hromadko ◽

Zdeněk Spotz ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Atomic Layer ◽

Vinyl Pyrrolidone ◽

Tio2 Photocatalyst ◽

Polymeric Fibers ◽

Layer Deposition ◽

Centrifugal Spinning ◽

Poly Vinyl Pyrrolidone

This work describes the synthesis of highly photocatalytically active TiO2 tubes (TiTBs) by combining centrifugal spinning and atomic layer deposition (ALD). Poly(vinyl pyrrolidone) (PVP) fibers were first produced by centrifugal...

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Potential Implantable Nanofibrous Biomaterials Combined with Stem Cells for Subchondral Bone Regeneration

Materials ◽

10.3390/ma13143087 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3087

Author(s):

Rana Smaida ◽

Luc Pijnenburg ◽

Silvia Irusta ◽

Erico Himawan ◽

Gracia Mendoza ◽

...

Keyword(s):

Stem Cells ◽

Bone Regeneration ◽

Subchondral Bone ◽

Therapeutic Potential ◽

Sodium Hyaluronate ◽

Vinyl Pyrrolidone ◽

Regenerative Ability ◽

Poly Vinyl Pyrrolidone

The treatment of osteochondral defects remains a challenge. Four scaffolds were produced using Food and Drug Administration (FDA)-approved polymers to investigate their therapeutic potential for the regeneration of the osteochondral unit. Polycaprolactone (PCL) and poly(vinyl-pyrrolidone) (PVP) scaffolds were made by electrohydrodynamic techniques. Hydroxyapatite (HAp) and/or sodium hyaluronate (HA) can be then loaded to PCL nanofibers and/or PVP particles. The purpose of adding hydroxyapatite and sodium hyaluronate into PCL/PVP scaffolds is to increase the regenerative ability for subchondral bone and joint cartilage, respectively. Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) were seeded on these biomaterials. The biocompatibility of these biomaterials in vitro and in vivo, as well as their potential to support MSC differentiation under specific chondrogenic or osteogenic conditions, were evaluated. We show here that hBM-MSCs could proliferate and differentiate both in vitro and in vivo on these biomaterials. In addition, the PCL-HAp could effectively increase the mineralization and induce the differentiation of MSCs into osteoblasts in an osteogenic condition. These results indicate that PCL-HAp biomaterials combined with MSCs could be a beneficial candidate for subchondral bone regeneration.

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In Vitro Drug Release, Permeability, and Structural Test of Ciprofloxacin-Loaded Nanofibers

Pharmaceutics ◽

10.3390/pharmaceutics13040556 ◽

2021 ◽

Vol 13 (4) ◽

pp. 556

Author(s):

Luca Éva Uhljar ◽

Sheng Yuan Kan ◽

Norbert Radacsi ◽

Vasileios Koutsos ◽

Piroska Szabó-Révész ◽

...

Keyword(s):

Amorphous State ◽

Physical Mixture ◽

Water Soluble ◽

Vinyl Pyrrolidone ◽

Amorphous Solid Dispersion ◽

Release Mechanism ◽

Dissolution Studies ◽

In Vitro Diffusion ◽

Poly Vinyl Pyrrolidone

Nanofibers of the poorly water-soluble antibiotic ciprofloxacin (CIP) were fabricated in the form of an amorphous solid dispersion by using poly(vinyl pyrrolidone) as a polymer matrix, by the low-cost electrospinning method. The solubility of the nanofibers as well as their in vitro diffusion were remarkably higher than those of the CIP powder or the physical mixture of the two components. The fiber size and morphology were optimized, and it was found that the addition of the CIP to the electrospinning solution decreased the nanofiber diameter, leading to an increased specific surface area. Structural characterization confirmed the interactions between the drug and the polymer and the amorphous state of CIP inside the nanofibers. Since the solubility of CIP is pH-dependent, the in vitro solubility and dissolution studies were executed at different pH levels. The nanofiber sample with the finest morphology demonstrated a significant increase in solubility both in water and pH 7.4 buffer. Single medium and two-stage biorelevant dissolution studies were performed, and the release mechanism was described by mathematical models. Besides, in vitro diffusion from pH 6.8 to pH 7.4 notably increased when compared with the pure drug and physical mixture. Ciprofloxacin-loaded poly(vinyl pyrrolidone) (PVP) nanofibers can be considered as fast-dissolving formulations with improved physicochemical properties.

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