کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5188749 1381168 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synthesis of methacrylated hyaluronic acid with tailored degree of substitution
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Synthesis of methacrylated hyaluronic acid with tailored degree of substitution
چکیده انگلیسی
The aim of this work was to develop a new method to derivatize hyaluronic acid (HyA) with polymerizable methacrylate residues with precise control over the substitution degree. The synthesis of methacrylated HyA (HyA-MA) was performed in dimethyl sulfoxide (DMSO) using glycidyl methacrylate (GMA) and 4-(N,N-dimethylamino)pyridine as a catalyst. HyA was rendered soluble in DMSO by exchanging the Na+ ions by the more lipophilic tetrabutylammonium ions. HyA-MA with a fully controlled degree of substitution (DS, defined as the number of methacrylate groups per 100 disaccharide units), ranging from 5 to 30, was obtained at 50 °C after 48 h. Hydrogels were obtained upon radical polymerization of aqueous solutions of HyA-MA using potassium peroxodisulfate (KPS) as initiator and N,N,N′,N′-tetramethylethylenediamine (TEMED) as catalyst. Almost complete methacrylate conversion (95%) was achieved for hydrogels obtained by polymerization of HyA-MA with a degree of substitution of 15. At lower DS (DS 8.5 and 5) the methacrylate conversion was 82% and 68%, respectively. Rheological characterization showed that with increasing DS the storage modulus of these HyA-MA hydrogels increased. Swelling experiments showed that HyA-MA gels with a DS of 15 or above were dimensionally stable, whereas HyA-MA gels with DS 5 and DS 8.5 swelled 1.6 and 1.4 times their initial weight, respectively. In conclusion, this paper shows that the DS of HyA-MA can be tailored by the reaction conditions and that consequently HyA-MA hydrogels with different characteristics can be prepared.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 48, Issue 7, 23 March 2007, Pages 1915-1920
نویسندگان
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