Polímeros: Ciência e Tecnologia
Polímeros: Ciência e Tecnologia
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Preparation and Structural Characterization of O-Acetyl Agarose with Low Degree of Substitution

Garcia, Rosangela B.; Vidal, Rosangela R. L.; Rinaudo, Marguerite

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Among the biodegradable polymers, the polysaccharides have been found to be promising carriers for bioactive molecules. From a general standpoint, they present several reactive groups, such as hydroxyl, carboxyl and amine, that can be modified in a number of ways, giving rise to suitable devices for controlled release. In this paper, agarose was submitted to O-acetylation reactions under heterogeneous conditions, using acetic anhydride and pyridine, aiming to observe the effect of acetyl groups on the agarose properties. The products were characterized by Infrared and 1H NMR spectroscopies. In the range of average acetylation degrees (DA) 0.07-0.48, the polymers presented partial solubility in boiling water and in common organic solvents. The 1H NMR spectra presented evidences of non-homogeneous acetyl group distribution along the chains, as concluded from the solubility of only one of the fractions with DA


Agarose, o-acetyl agarose, acetylation


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