Rapid Accessible Fabrication and Engineering of Bilayered Hydrogels: Revisiting the Cross-Linking Effect on Superabsorbent Poly(acrylic acid)

Poly(acrylic acid) (PAAc) hydrogels possess good bioadhesive properties and allow enhanced penetration of drugs. In addition, it is possible to localize the absorption site of the drug in the hydrogel and increase the drug residence time. As opposed to other cross-linking processes radiation-induced polymer cross-linking can be easily and rapidly carried out without the use of cross-linking agents and other chemical additives. In this study, we fabricated metronidazole (MD) containing PAAc hydrogel (MD/PAAc) with different MD contents (0.1, 0.25, 0.5 wt%) using varying radiation doses (25, 50, 75 kGy) by gamma-irradiation. The physical and thermal properties were determined by gel content analysis, swelling ratio measurements, compressive strength measurements, differential scanning calorimetery, and thermogravimetric analysis. The properties of the hydrogel degraded due to the crystalline nature of MD. The properties of the hydrogel degraded due to the crystalline nature of MD. Cumulative release observed after 50 min in the case of 0.5MD/PAAc and 0.1MD/PAAc was 50% and 10%, respectively. Our findings suggest that MD/PAAc could be a suitable drug delivery carrier for use with radiation-based techniques.

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Radiation synthesis of poly(acrylic acid) nanogels for drug delivery applications – post-synthesis product colloidal stability

Nukleonika ◽

10.2478/nuka-2021-0026 ◽

2021 ◽

Vol 66 (4) ◽

pp. 179-186

Author(s):

Beata P. Rurarz ◽

Natalia Gibka ◽

Małgorzata Bukowczyk ◽

Sławomir Kadłubowski ◽

Piotr Ulański

Keyword(s):

Drug Delivery ◽

Acrylic Acid ◽

Colloidal Stability ◽

Biologically Active ◽

Cross Linking ◽

Synthesis Product ◽

High Dose ◽

Water Radiolysis ◽

Drug Delivery Applications ◽

Poly Acrylic Acid

Abstract Synthesis of polymer nanogels (NGs) for biomedical applications is considered to be a very promising application in radiation engineering. Under high-dose pulse irradiation of dilute aqueous polymer solution, reactive species generated by water radiolysis can create multiple radicals on each macromolecule and consequently induce intramolecular cross-linking of polymer chains, resulting in NG formation. The obtained products are free from harmful monomers, initiators, and cross-linking agents, which makes them potentially applicable for drug delivery applications. One of the biggest challenges in handling and use of nanoparticles, however, is the colloidal stability, when aqueous suspensions are stored for prolonged periods. Therefore, development of the best protocols for the particular nanocarrier storage is key. To address this need, we have performed the prospective study in which we systematically assessed the influence of various processing and storage scenarios feasible in our lab, on the colloidal stability of the radiation-synthesized poly(acrylic acid) (PAA) NG particles in suspension. This allowed us to choose the optimal way of handling the product after its synthesis. We confirmed that none of the strategies we used and tested are substantially detrimental to our product. Filtration with 0.2-μm filters was proven sufficient for sample purification and prolonged storage in aqueous suspension did not exert a negative effect on the colloidal stability of particles suspension. We have also demonstrated that lyoprotectant-free lyophilization was suitable for our polymer nanoparticles. This is an important fact for further application of particles as nanocarriers for biologically active compounds such as targeting ligands or therapeutic moieties.

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γ-Irradiation Induced Synthesis of Titanium Dioxide/Poly(acrylic acid) (TiO2/PAA) Nanocomposites and Layer-by-Layer Assembly on Glass Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1098.25 ◽

2015 ◽

Vol 1098 ◽

pp. 25-30 ◽

Cited By ~ 1

Author(s):

Lawrence John Paulo L. Trinidad ◽

Ken Aldren S. Usman ◽

Leon M. Payawan

Keyword(s):

Acrylic Acid ◽

Layer Thickness ◽

Titania Nanoparticles ◽

Cross Linking ◽

Layer By Layer ◽

Γ Irradiation ◽

Sem Images ◽

Nucleation Sites ◽

Anatase Titania ◽

Poly Acrylic Acid

Adsorption and encapsulation of the nanoparticles in polyelectrolytes impart stability to the nanometal by preventing aggregation through electrostatic and steric effects. Poly (acrylic acid) (PAA) was employed as a polymer cap to anatase titania nanoparticles. Cross-linking of the polymer was done via free-radical cross-linking using gamma-irradiation. The size of the nanocomposite produced ranged from 40-120 nm. SEM images showed that excess TiO2 in solution becomes nucleation sites for aggregation. Film assembly of the synthesized nanocomposite were done by layer-by-layer deposition with PDDA. Films formed with increasing thickness (5, 10, and 15 layers) were analyzed under AFM and shown to have a thickness of 0.25 μm, 1.1μm and 3.0 μm respectively.The average film layer thickness obtained ranged from 50-200 nm per TiO2/PAA-PDDA layer where as the number of layers deposited increase, the layer thickness increase while the roughness decreases.

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Understanding why poly(acrylic acid) works: decarbonylation and cross-linking provide an ionically conductive passivation layer in silicon anodes

Journal of Materials Chemistry A ◽

10.1039/d1ta04319f ◽

2021 ◽

Vol 9 (38) ◽

pp. 21929-21938

Author(s):

Trevor R. Martin ◽

Ryan T. Pekarek ◽

Jaclyn E. Coyle ◽

Maxwell C. Schulze ◽

Nathan R. Neale

Keyword(s):

Acrylic Acid ◽

Passivation Layer ◽

Cross Linking ◽

Silicon Anodes ◽

Li Ion ◽

Silicon Coating ◽

Poly Acrylic Acid

PAA undergoes decarbonylation during electrode curing to form polyethers that provide a silicon coating that assists Li-ion desolvation and conduction.

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