|کد مقاله||کد نشریه||سال انتشار||مقاله انگلیسی||ترجمه فارسی||نسخه تمام متن|
|5184447||1381048||2011||10 صفحه PDF||سفارش دهید||دانلود رایگان|
Viability of encapsulated cells in situ crosslinkable macromonomers depends strongly on the minimum concentration of polymerization initiators and monomers required for gelation. Novel 4-arm poly(ethylene oxide-co-lactide-glycolide acrylate) (SPELGA) macromonomers were synthesized and characterized with respect to gelation, sol fraction, degradation, and swelling in aqueous solution. SPELGA macromonomers were crosslinked in the absence of N-vinyl-2-pyrrolidone (NVP) monomer to produce a hydrogel network with a shear modulus of 27Â Â±Â 4Â kPa. The shear modulus of the gels increased by 170-fold as the macromonomer concentration was increased from 10 to 25Â wt%. Sol fraction ranged between 8 and 18%. Addition of only 0.4Â mol% NVP to the polymerization mixture increased modulus by 2.2-fold from 27Â Â±Â 4 (no NVP) to 60Â Â±Â 10Â kPa. The higher modulus was attributed to the dilution effect of polymer chains in the sol, by delaying the onset of diffusion-controlled reaction, and cross-propagation of the growing chains with network-bound SPELGA acrylates. Degradation of SPELGA gels depended on water content and density of hydrolytically degradable ester groups.
A multi-armamphiphilic poly(ethylene oxide-co-lactide-glycolide acrylate) (SPELGA) macromonomer is synthesized to produce a mechanically-robust degradable hydrogel network at minimum required concentration of initiator with low sol fraction. These hydrogel networks are potentially useful as a degradable carrier in drug delivery and cell-based therapies.
Journal: Polymer - Volume 52, Issue 18, 18 August 2011, Pages 3887-3896