Novel Preparation of Poly(Vinyl Alcohol) Microparticles without Crosslinking Agent for Controlled Drug Delivery

1993 ◽  
Vol 331 ◽  
Author(s):  
Becky J. Ficek ◽  
Nicholas A. Peppas
Keyword(s):  
Vinyl Alcohol ◽  
Corn Oil ◽  
Crosslinking Agent ◽  
Degree Of Crystallinity ◽  
Poly Vinyl Alcohol ◽  
Release Mechanism ◽  
Lauryl Sulfate ◽  
Freezing And Thawing ◽  
Scanning Calorimetry ◽  
Thawing Process

AbstractPoly(vinyl alcohol) microparticles were prepared by a novel freezing-thawing process in the absence of a crosslinking agent. An aqueous PVA solution to which 1.25 wt% sodium lauryl sulfate was added was dispersed in corn oil. The system was agitated and the ensuing suspended droplets of PVA solution were solidified by a cyclic freezing-thawing process. Key parameters of the process were the PVA to corn oil ratio, the amount of surfactant added, agitation speed, number of freeze cycles, temperatures of freezing and thawing, and presence of additional components.Crystallization was observed during the freezing-thawing process. The degree of crystallinity was measured with differential scanning calorimetry. Bovine serum albumin was incorporated into the particles by an absorption technique. Studies of BSA release from the microparticles in vitro showed that the release could be prolonged for up to 7 days. BSA diffusion coefficients were calculated from these data and the release mechanism was identified.

scholarly journals Effect of Poly(vinyl alcohol) on Nanoencapsulation of Budesonide in Chitosan Nanoparticles via Ionic Gelation and Its Improved Bioavailability

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1101 ◽  
Author(s):  
Georgia Michailidou ◽  
Nina Maria Ainali ◽  
Eleftheria Xanthopoulou ◽  
Stavroula Nanaki ◽  
Margaritis Kostoglou ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Computational Study ◽  
Chitosan Nanoparticles ◽  
In Vitro Release ◽  
Degree Of Crystallinity ◽  
Poly Vinyl Alcohol ◽  
Dissolution Profile ◽  
Ionic Gelation ◽  
Scanning Calorimetry

Chitosan (CS) is a polymer extensively used in drug delivery formulations mainly due to its biocompatibility and low toxicity. In the present study, chitosan was used for nanoencapsulation of a budesonide (BUD) drug via the well-established ionic gelation technique and a slight modification of it, using also poly(vinyl alcohol) (PVA) as a surfactant. Scanning electron microscopy (SEM) micrographs revealed that spherical nanoparticles were successfully prepared with average sizes range between 363 and 543 nm, as were measured by dynamic light scattering (DLS), while zeta potential verified their positive charged surface. X-ray diffraction (XRD) patterns revealed that BUD was encapsulated in crystalline state in nanoparticles but with a lower degree of crystallinity than the neat drug, which was also proven by differential scanning calorimetry (DSC) and melting peak measurements. This could be attributed to interactions that take place between BUD and CS, which were revealed by FTIR and by an extended computational study. An in vitro release study of budesonide showed a slight enhancement in the BUD dissolution profile, compared to the neat drug. However, drug release was substantially increased by introducing PVA during the nanoencapsulation procedure, which is attributed to the higher amorphization of BUD on these nanoparticles. The release curves were analyzed using a diffusion model that allows estimation of BUD diffusivity in the nanoparticles.

Characterization of Genipin Crosslinked Hydrogels Composed of Chitosan and Partially Hydrolyzed Poly(vinyl alcohol)

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Ashveen V. Nand ◽  
David R. Rohindra ◽  
Jagjit R. Khurma
Keyword(s):  
Vinyl Alcohol ◽  
Crosslinking Agent ◽  
Bound Water ◽  
Deionized Water ◽  
Swelling Behavior ◽  
Poly Vinyl Alcohol ◽  
Interpenetrating Networks ◽  
Scanning Calorimetry ◽  
Naturally Occurring

AbstractChitosan and 80 % hydrolyzed poly(vinyl alcohol) (PVA) were used to prepare semi-interpenetrating networks of varying ratios of the constituents. The hydrogels were crosslinked using genipin, a naturally occurring nontoxic crosslinking agent. The swelling behavior of these hydrogels was studied in deionized water at 25, 35 and 45 °C and in media of different pH at 25 °C. The swelling behavior of the gels was found to be dependent on temperature, pH of the medium and the amount of PVA present in the gel. States of water in the hydrogels swollen at 25 °C and pH 7 were determined using Differential Scanning Calorimetry (DSC). The amount of freezing water in the swollen hydrogels increased whereas the amount of nonfreezing bound water decreased with the increase in PVA concentration in the gels. The gelation behaviour of the pregel solutions were also studied.

scholarly journals Impact of the Type of Crosslinking Agents on the Properties of Modified Sodium Alginate/Poly(vinyl Alcohol) Hydrogels

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2381
Author(s):  
Katarzyna Bialik-Wąs ◽  
Ewelina Królicka ◽  
Dagmara Malina
Keyword(s):  
Sodium Alginate ◽  
Aqueous Extract ◽  
Vinyl Alcohol ◽  
Crosslinking Agent ◽  
Echinacea Purpurea ◽  
Poly Vinyl Alcohol ◽  
Spectra Analysis ◽  
Natural Origin ◽  
Glycol Diacrylate ◽  
Soxhlet Apparatus

Here, we report on studies on the influence of different crosslinking methods (ionic and chemical) on the physicochemical (swelling ability and degradation in simulated body fluids), structural (FT-IR spectra analysis) and morphological (SEM analysis) properties of SA/PVA hydrogels containing active substances of natural origin. First, an aqueous extract of Echinacea purpurea was prepared using a Soxhlet apparatus. Next, a series of modified SA/PVA-based hydrogels were obtained through the chemical crosslinking method using poly(ethylene glycol) diacrylate (PEGDA, Mn = 700 g/mol) as a crosslinking agent and, additionally, the ionic reaction in the presence of a 5% w/v calcium chloride solution. The compositions of SA/PVA/E. purpurea-based hydrogels contained a polymer of natural origin—sodium alginate (SA, 1.5% solution)—and a synthetic polymer—poly(vinyl alcohol) (PVA, Mn = 72,000 g/mol, 10% solution)—in the ratio 2:1, and different amounts of the aqueous extract of E. purpurea—5, 10, 15 or 20% (v/v). Additionally, the release behavior of echinacoside from the polymeric matrix was evaluated in phosphate-buffered saline (PBS) at 37 °C. The results indicate that the type of the crosslinking method has a direct impact on the release profile. Consequently, it is possible to design a system that delivers an active substance in a way that depends on the application.

Reinforcement with cellulose nanocrystals of poly(vinyl alcohol) hydrogels prepared by cyclic freezing and thawing

Soft Matter ◽  
2011 ◽  
Vol 7 (6) ◽  
pp. 2373 ◽  
Author(s):  
Tiffany Abitbol ◽  
Timothy Johnstone ◽  
Thomas M. Quinn ◽  
Derek G. Gray
Keyword(s):  
Cellulose Nanocrystals ◽  
Vinyl Alcohol ◽  
Poly Vinyl Alcohol ◽  
Freezing And Thawing

scholarly journals Structural Organization of Poly(vinyl alcohol) Hydrogels Obtained by Freezing and Thawing Techniques:  A SANS Study

2005 ◽  
Vol 17 (5) ◽  
pp. 1183-1189 ◽  
Author(s):  
Rosa Ricciardi ◽  
Gaetano Mangiapia ◽  
Fabrizio Lo Celso ◽  
Luigi Paduano ◽  
Roberto Triolo ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Structural Organization ◽  
Poly Vinyl Alcohol ◽  
Freezing And Thawing

scholarly journals PREPARATION AND CHARACTERIZATION OF POLY (VINYL ALCOHOL)–POLY (VINYL PYRROLIDONE) MUCOADHESIVE BUCCAL PATCHES FOR DELIVERY OF LIDOCAINE HCL

2018 ◽  
Vol 10 (1) ◽  
pp. 115 ◽  
Author(s):  
Napaphak Jaipakdee ◽  
Thaned Pongjanyakul ◽  
Ekapol Limpongsa
Keyword(s):  
Vinyl Alcohol ◽  
Vinyl Pyrrolidone ◽  
Poly Vinyl Alcohol ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Casting Technique ◽  
In Vitro Permeation ◽  
Lidocaine Hcl ◽  
Poly Vinyl Pyrrolidone

Objective: The objectives of this study were to prepare and characterize a buccal mucoadhesive patch using poly (vinyl alcohol) (PVA), poly (vinyl pyrrolidone) (PVP) as a mucoadhesive matrix, Eudragit S100 as a backing layer, and lidocaine HCl as a model drug.Methods: Lidocaine HCl buccal patches were prepared using double casting technique. Molecular interactions in the polymer matrices were studied using attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and X-ray diffractometry. Mechanical and mucoadhesive properties were measured using texture analyzer. In vitro permeation of lidocaine HCl from the patch was conducted using Franz diffusion cell.Results: Both of the free and lidocaine HCl patches were smooth and transparent, with good flexibility and strength. ATR-FTIR, DSC and X-ray diffractometry studies confirmed the interaction of PVA and PVP. Mechanical properties of matrices containing 60% PVP were significantly lower than those containing 20% PVP (*P<0.05). Mucoadhesive properties had a tendency to decrease with the concentration of PVP in the patch. The patch containing 60% PVP had significantly lower muco-adhesiveness than those containing 20% PVP (*P<0.05). In vitro permeation revealed that the pattern of lidocaine HCl permeation started with an initial fast permeation, followed by a slower permeation rate. The initial permeation fluxes follow the zero-order model of which rate was not affected by the PVP concentrations in the PVA/PVP matrix.Conclusion: Mucoadhesive buccal patches fabricated with PVA/PVP were successfully prepared. Incorporation of PVP in PVA/PVP matrix affected the strength of polymeric matrix and mucoadhesive property of patches.

Physical and mechanical investigation for polyionic liquid/poly(vinyl alcohol) blends

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nehad N. Rozik ◽  
Emad Saad Shafik ◽  
Salwa L. Abd-El-Messieh
Keyword(s):  
Mechanical Properties ◽  
Vinyl Alcohol ◽  
Green Manufacturing ◽  
Poly Vinyl Alcohol ◽  
Scanning Calorimetry ◽  
Content Type ◽  
Content Ratio ◽  
Mechanical Investigation ◽  
Manufacturing Techniques ◽  
Polyionic Liquid

Purpose This study aims to polymerize of 1-butyl-3-vinylimidazolium bromide (PIL). PIL was embedded into PVA with a different content ratio by casting method. This research also deals with the effect of adding PIL in different proportions to PVA on the electrical and mechanical properties properties in addition to the morphology of the prepared samples. Design/methodology/approach 1-Butyl-3-vinylimidazolium bromide was synthesized through quaternization and free radical polymerization. The resulting polymer was characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis and differential scanning calorimetry. In addition to the morphology of PVA, PVA/PIL was investigated by polarizing microscope. Also, the effect of PIL content on the electrical and mechanical properties was evaluated. Findings The findings of this study might lead to new applications for PVA and PILs in electrical and dielectrics. The mechanical results revealed that the tensile strength increased slightly with increasing polyionic liquid (PIL) content and decreased above 10% PIL. While the elongation at break increased significantly with increasing PIL content and begin to decrease above 10% PIL. Also, the electrical property of the poly(vinyl alcohol) (PVA)/PIL blends was improved because of the strong plasticizing effect of PIL. Also, the electrical conductivity of these polymer electrolytes is greatly increased. This indicates that the imidazolium-based PIL has an effective approach that leads to an increase in the conductivity of the polymer. The PILs/PVA design will not only enrich the chemical structure but also will contribute to green manufacturing techniques and a processing methodology that enables green membrane manufacture. Originality/value This study contributes to green manufacturing techniques and a processing methodology that enables “green” membrane manufacture.

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