Diverse actions of added alkanols on the binding of dibucaine cation to an anionic polymer

The application of an oppositely charged dual polymer system is a promising approach to enhance paper strength. In this work, modified chitosan (MCN), a cationic polymer, and carboxymethyl cellulose (CMC), an anionic polymer, were used sequentially to improve paper strength. The adsorption of MCN on cellulose fibers was analyzed via polyelectrolyte titration. The formation of MCN/CMC complex in water and the deposition of this complex on silicon wafers were investigated by means of atomic force microscope and quasi-elastic light scattering techniques. The results showed that paper strength was enhanced slightly with a layer-by-layer assembly of the polymers. However, if the washing stage, which was required for layer-by-layer assembly, was eliminated, the MCN/CMC complex was deposited on fibers more efficiently, and the paper strength was improved more significantly. The significant improvement was attributed to the extra development of fiber bonding, confirmed further by scanning electron microscope observation of the bonding area of fibers treated with or without washing. However, the brightness of papers was somewhat decreased by the deposition of the complex on fibers. Higher paper strength also was achieved using rapid drying rather than air drying.

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An Update on the Use of Alginate in Additive Biofabrication Techniques

Current Pharmaceutical Design ◽

10.2174/1381612825666190423155835 ◽

2019 ◽

Vol 25 (11) ◽

pp. 1249-1264 ◽

Cited By ~ 2

Author(s):

Amoljit Singh Gill ◽

Parneet Kaur Deol ◽

Indu Pal Kaur

Keyword(s):

Fused Deposition Modeling ◽

Low Cost ◽

Selective Laser Sintering ◽

Layer By Layer ◽

Three Dimension ◽

Anionic Polymer ◽

Fused Deposition ◽

The Status ◽

Deposition Modeling ◽

Extrusion Printing

Background: Solid free forming (SFF) technique also called additive manufacturing process is immensely popular for biofabrication owing to its high accuracy, precision and reproducibility. Method: SFF techniques like stereolithography, selective laser sintering, fused deposition modeling, extrusion printing, and inkjet printing create three dimension (3D) structures by layer by layer processing of the material. To achieve desirable results, selection of the appropriate technique is an important aspect and it is based on the nature of biomaterial or bioink to be processed. Result & Conclusion: Alginate is a commonly employed bioink in biofabrication process, attributable to its nontoxic, biodegradable and biocompatible nature; low cost; and tendency to form hydrogel under mild conditions. Furthermore, control on its rheological properties like viscosity and shear thinning, makes this natural anionic polymer an appropriate candidate for many of the SFF techniques. It is endeavoured in the present review to highlight the status of alginate as bioink in various SFF techniques.

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Influence of spin finish on degradation, functionalization and long-term storage of polyethylene terephthalate fabrics dedicated to ligament prostheses

Scientific Reports ◽

10.1038/s41598-021-83572-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tuan Ngoc Nguyen ◽

Andre Rangel ◽

David W. Grainger ◽

Véronique Migonney

Keyword(s):

Young’S Modulus ◽

Polyethylene Terephthalate ◽

Uv Light ◽

Young's Modulus ◽

Cruciate Ligament ◽

Surface Cleaning ◽

Anionic Polymer ◽

Pet Fabric ◽

Oil Storage ◽

Grafting Degree

AbstractPolyethylene terephthalate (PET) fibers and fabrics are widely used for medical device applications such as vascular and anterior cruciate ligament prostheses. Several years ago, we began functionalizing PET fabrics using anionic polymers to enhance their biocompatibility, cell adhesion, proliferation and functional performance as PET ligament prostheses. Polymer functionalization followed a grafting-from process from virgin PET surfaces subject to spin-finish oil additive removal under Soxhlet extraction to remove residual fiber manufacturing oil. Nevertheless, with increasing time from manufacture, PET fabrics stored without a spin finish removal step exhibited degradation of spin finish oil, leading to (1) incomplete surface cleaning, and (2) PET surface degradation. Moreover, oxidizing agents present in the residual degraded oil prevented reliable functionalization of the prosthesis fibers in these PET fabrics. This study compares effects of PET fabric/spin finish oil storage on PET fabric anionic polymer functionalization across two PET fabric ligament storage groups: (1) 2- and 10- year old ligaments, and (2) 26-year old ligaments. Strong interactions between degraded spin finish oil and PET fiber surfaces after long storage times were demonstrated via extraction yield; oil chemistry changed assessed by spectral analysis. Polymer grafting/functionalization efficiency on stored PET fabrics was correlated using atomic force microscopy, including fiber surface roughness and relationships between grafting degree and surface Young’s modulus. New PET fabric Young’s modulus significantly decreased by anionic polymer functionalization (to 96%, grafting degree 1.6 µmol/g) and to reduced modulus and efficiency (29%) for 10 years storage fabric (grafting degree ~ 1 µmol/g). As fiber spin finish is mandatory in biomedically applicable fiber fabrication, assessing effects of spin finish oil on commercial polymer fabrics after longer storage under various conditions (UV light, temperature) is necessary to understand possible impacts on fiber degradation and surface functionalization.

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Gum Tragacanth (GT): A Versatile Biocompatible Material beyond Borders

Molecules ◽

10.3390/molecules26061510 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1510 ◽

Cited By ~ 2

Author(s):

Mohammad Ehsan Taghavizadeh Yazdi ◽

Simin Nazarnezhad ◽

Seyed Hadi Mousavi ◽

Mohammad Sadegh Amiri ◽

Majid Darroudi ◽

...

Keyword(s):

Tissue Engineering ◽

Food Packaging ◽

Three Dimensional ◽

Great Promise ◽

Anionic Polymer ◽

Gum Tragacanth ◽

New Horizons ◽

Tissue Healing ◽

The Stability ◽

Therapeutic Substance

The use of naturally occurring materials in biomedicine has been increasingly attracting the researchers’ interest and, in this regard, gum tragacanth (GT) is recently showing great promise as a therapeutic substance in tissue engineering and regenerative medicine. As a polysaccharide, GT can be easily extracted from the stems and branches of various species of Astragalus. This anionic polymer is known to be a biodegradable, non-allergenic, non-toxic, and non-carcinogenic material. The stability against microbial, heat and acid degradation has made GT an attractive material not only in industrial settings (e.g., food packaging) but also in biomedical approaches (e.g., drug delivery). Over time, GT has been shown to be a useful reagent in the formation and stabilization of metal nanoparticles in the context of green chemistry. With the advent of tissue engineering, GT has also been utilized for the fabrication of three-dimensional (3D) scaffolds applied for both hard and soft tissue healing strategies. However, more research is needed for defining GT applicability in the future of biomedical engineering. On this object, the present review aims to provide a state-of-the-art overview of GT in biomedicine and tries to open new horizons in the field based on its inherent characteristics.

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Isolation of infectious chikungunya virus and dengue virus using anionic polymer-coated magnetic beads

Journal of Virological Methods ◽

10.1016/j.jviromet.2013.04.016 ◽

2013 ◽

Vol 193 (1) ◽

pp. 55-61 ◽

Cited By ~ 14

Author(s):

Sirilaksana Patramool ◽

Eric Bernard ◽

Rodolphe Hamel ◽

Luplertlop Natthanej ◽

Nathalie Chazal ◽

...

Keyword(s):

Dengue Virus ◽

Chikungunya Virus ◽

Magnetic Beads ◽

Anionic Polymer

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Foamability and Stability of Anionic Surfactant-Anionic Polymer Solutions: Influence of Ionic Strength, Polymer Concentration, and Molecular Weight

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2021.127801 ◽

2021 ◽

pp. 127801

Author(s):

Abduljelil S. Kedir ◽

Jonas S. Solbakken ◽

Morten G. Aarra

Keyword(s):

Molecular Weight ◽

Ionic Strength ◽

Anionic Surfactant ◽

Polymer Solutions ◽

Polymer Concentration ◽

Anionic Polymer

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Optimized Chitosan/Anion Polyelectrolyte Complex Based Inserts for Vaginal Delivery of Fluconazole: In Vitro/In Vivo Evaluation

Pharmaceutics ◽

10.3390/pharmaceutics10040227 ◽

2018 ◽

Vol 10 (4) ◽

pp. 227 ◽

Cited By ~ 9

Author(s):

Bayan Darwesh ◽

Hibah Aldawsari ◽

Shaimaa Badr-Eldin

Keyword(s):

Vaginal Delivery ◽

Polyelectrolyte Complex ◽

Inflammatory Cells ◽

Antifungal Drugs ◽

Vaginal Candidiasis ◽

Histological Evaluation ◽

Anionic Polymer ◽

In Vivo Evaluation

(1) Background: Fluconazole, used orally for vaginal candidiasis, has reported gastrointestinal side effects. Therefore, researchers directed towards the drug vaginal delivery. However, vaginal delivery is limited by poor retention and leakage. Thus, this work aimed at exploring chitosan/anion polyelectrolyte complex (PEC) for the formulation of fluconazole vaginal inserts with controlled release and appreciable mucoadhesion. (2) Methods: PECs were prepared and assessed for interactions. Fluconazole PEC based vaginal inserts were prepared by lyophilization using mannitol. 3151 factorial design was applied to investigate the effect of the anion type and Chitosan/anion ratio on the inserts mucoadhesion and release properties. The optimized insert [based on 5:5 chitosan: anionic polymer (sodium alginate)] release was modulated by the release retardant; Compritol® 888. The selected formulation was subjected to microbiological and histological evaluation. (3) Results: Fluconazole inserts showed satisfactory drug content, acceptable friability percentages and highest swelling indices at six hours. Statistical analysis showed significant effect of the studied factors on detachment force and release properties. Microbiological assays revealed significantly higher antifungal activity of inserts compared to fluconazole solution. Reduced inflammatory cells were confirmed by histological evaluation. (4) Conclusion: CH/Alg based vaginal insert could be a promising platform for vaginal delivery of antifungal drugs used for vaginal candidiasis treatment.

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Addition of Tubifex accelerates dewatering of oil sands tailings

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2016-0308 ◽

2016 ◽

Vol 43 (12) ◽

pp. 1025-1033 ◽

Cited By ~ 1

Author(s):

Xiaojuan Yang ◽

Miguel de Lucas Pardo ◽

Maria Ibanez ◽

Lijun Deng ◽

Luca Sittoni ◽

...

Keyword(s):

Oil Sands ◽

Land Reclamation ◽

Test Results ◽

Anionic Polymer ◽

Fine Tailings ◽

Fluid Fine Tailings ◽

Oil Sands Tailings ◽

Set Up ◽

Solids Content

Accelerating dewatering of fluid fine tailings (FFT) to facilitate land reclamation is a major challenge to the oil sands industry in Canada. A new method was tested, addition of Tubifex to FFT. Tubifex is an indigenous earthworm in Canada. The survival rate tests showed that Tubifex can survive in oil sands tailings and penetrate to 42 cm depth (maximum depth tested). Columns (5 L of FFT) were set-up with tailings alone, Tubifex treated tailings and polymer-Tubifex treated tailings. Test results showed that (a) the final mud–water interface of tailings alone was 26% higher than that of Tubifex treated tailings; (b) solids content of Tubifex treated tailings was 21% more than that of tailings alone; (c) Tubifex was capable to accelerate the dewatering process of both cationic and anionic polymer treated tailings; (d) anionic polymer was superior in facilitating long-term dewatering and its coupled effects with Tubifex were better than the cationic polymer.

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