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1.
Macromol Rapid Commun ; 35(8): 794-800, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24700443

RESUMO

A straightforward and expeditious monotopic approach for the preparation of 1,2,3-triazolium-based poly(ionic liquids) (TPILs) is reported. It is based on the solvent- and catalyst-free polyaddition of an α-azide-ω-alkyne monomer in the presence of methyl iodide or N-methyl bis[(trifluoromethyl)sulfonyl]imide alkylating agents. Poly(1,2,3-triazole)s generated in bulk or by thermal azide-alkyne cycloaddition (AAC) are quaternized in-situ to afford TPILs composed of 1,3,4- and 1,3,5-trisubstituted 1,2,3-triazolium units. The physical and ion-conducting properties of the prepared samples are compared with the TPILs composed solely of 1,3,4-trisubstituted 1,2,3-triazolium units obtained through a multistep approach involving copper(I)-catalyzed AAC polyaddition, quaternization of the 1,2,3-triazole groups, and anion metathesis. TPILs obtained through the monotopic approach display thermal stabilities and ionic conductivities comparable to their pure regioisomeric analogues.


Assuntos
Líquidos Iônicos/síntese química , Polímeros/síntese química , Triazóis/química , Alquilantes/química , Catálise , Hidrocarbonetos Iodados/química , Líquidos Iônicos/química , Íons/química , Modelos Químicos , Estrutura Molecular , Polímeros/química , Espectroscopia de Prótons por Ressonância Magnética , Solventes , Estereoisomerismo , Temperatura , Fatores de Tempo
2.
ACS Biomater Sci Eng ; 8(4): 1735-1748, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35226455

RESUMO

The wet spinning of cytocompatible, bioresorbable, and knittable chitosan (CTS) monofilaments would be advantageous for a variety of surgical applications. The complexation capacity of chitosan with Cu2+ or Zn2+ can be leveraged to enhance its antibacterial activity, but not at the expense of cytocompatibility. In this work, a wet-spinning process was adapted for the in situ incorporation of Cu2+ or Zn2+ with chitosan dopes to produce monofilaments at different drawing ratios (τtot) with various cation/glucosamine molar ratios, evaluated in the fibers (rCu,f and rZn,f). Cytocompatibility and antibacterial activity of wet-spun monofilaments were, respectively, quantified by in vitro live-dead assays on balb 3T3 and by different evaluations of the proliferation inhibition of Staphylococcus epidermidis (Gram+) and Escherichia coli (Gram-). Knittability was tested by a specific tensile test using a knitting needle and evaluated with an industrial knitting machine. It was found that rCu,f = 0.01 and rZn,f = 0.03 significantly increase the antibacterial activity without compromising cytocompatibility. Wet spinning with τtot = 1.6 allowed the production of knittable CTS-Cu monofilaments, as confirmed by knitting assays under industrial conditions.


Assuntos
Quitosana , Antibacterianos/farmacologia , Quitosana/farmacologia , Escherichia coli , Zinco/farmacologia
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