Copolymers of 2-hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA), and terpolymers of HEMA, MMA, and methacrylic acid (MA) were synthesized in the presence of N,N'-bis(methacryloyloxyethyloxycarbonylamino)azobenzene (B(MOEOCA)AB) and evaluated as coating materials for colonic targeting. The release of ibuprofen, a model drug, from capsules coated with the azo polymers was investigated in vitro. The release medium was made up of sonicated rat cecal content, benzyl viologen, glucose-6-phosphate, glucose-6-phosphate dehydrogenase, and nicotine amide dinucleotide phosphate (NADP) in phosphate buffer (pH 6.8, 0.05M). The drug-release profiles indicate that the degradation of the azo polymer coatings depends on their degree of swelling, due to a higher accessibility of the azo bonds for the bacterial azo reductase. The best results were obtained with azo polymers containing MA: 98.7 (+/- 1.1) % of ibuprofen was released after 19 hours residence in the release medium, while only 26.2 (+/- 4.9) % in the control experiment. These findings demonstrate that azo polymers are promising materials for delivering drugs selectivity to the colon.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1023/a:1018911316021 | DOI Listing |
Int J Biol Macromol
January 2025
Department of Polymer Materials and Engineering, College of Materials and Metallurgy, Guizhou University, Guiyang 550025, China. Electronic address:
Gold nanoparticles (AuNPs) with ultra-small size anchored onto support materials is highly desired towards good catalytic performance. In this study, aldehyde-functionalized chitin nanocrystals (ChNCs-PVMA) are prepared by surface-initiated electron transfer atom transfer radical polymerization (SI-ARGET ATRP) with vanillin methacrylate (VMA) as a functional monomer, which are used as reductant, stabilizer and support for the fabrication of AuNPs through an environmentally friendly process that eliminates the need for any additional reducing agents. The abundant aldehyde groups of the prepared ChNCs-PVMA are crucial to achieve ultra-small AuNPs with average size of 5.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Sklodowska Str., 41-819 Zabrze, Poland.
In this study, a polymer gel electrolyte based on polyacrylonitrile was synthesized with varying polymer-to-liquid-electrolyte ratios. DSSCs incorporating a 1:3 ratio showed optimum PV parameters. Choosing this proportion, the effect of incorporating the photoresponsive AZO dye into this polymer electrolyte was studied.
View Article and Find Full Text PDFSci Rep
January 2025
Faculty of Physics, Warsaw University of Technology, 75 Koszykowa Str., 00-662, Warszawa, Poland.
Surface relief grating formation in photo-responsive azo polymers under irradiation is a long-ago-found phenomenon, but all the factors governing its efficiency are still not fully recognized. Here, we report on the enormous impact of the polymer thickness on the possibility of fabrication of extremely high-amplitude surface deformations. We performed prolonged holographic recordings on the layers of the same azobenzene poly(ether imide), which had substantially different optical transmittances at the recording wavelength and revealed that the depths of the inscribed relief structures increased with the polymer thickness from a nondetectable value up to almost 2 µm, unaffected by the presence of a polymer-glass substrate interface in either sample.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Materials Polymer Laboratory, Macromolecular Chemistry Department, Faculty of Chemistry, University of Sciences and Technology Houari Boumediene USTHB, B.P. 32 El-Alia, 16111 Algiers, Algeria.
Herein, we propose magnetic nanocomposites as a powerful new catalyst for organic pollutant reduction. Polypyrrole (PPy) was synthesized in situ within the semi-interpenetrating alginate (Alg)/gelatin (Ge) network in presence of α-FeO as encapsulating matrix and inorganic filler, respectively. The polymeric matrix can act as bifunctional agent such as a binder and stabilizer to improve nanocatalyst stability while preserving their catalytic/magnetic performances.
View Article and Find Full Text PDFTalanta
December 2024
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences & Chongqing School, University of Chinese Academy of Science, Chongqing, 400714, PR China. Electronic address:
Owing to the facile fabrication and surface modification, the cost-effective polymer nanopores are widely employed in unimolecular determination of biomacromolecules and selective sensing of small molecules, nanoparticles and biomarkers. However, the documented polymer nanochannels are generally microscale in length with low spatial resolution. We herein synthesized azobenzene side-chain polymer (Azo-PMA) and spin-coated on silicon nitride membrane to obtain a polymer film of nanoscale thickness for further nanopore generation via controlled dielectric breakdown (CDB) approach.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!