Thermosensitive injectable hyaluronic acid hydrogel for adipose tissue engineering

摘要: Abstract A series of thermosensitive copolymer hydrogels, aminated hyaluronic acid-g-poly(N-isopropylacrylamide) (AHA-g-PNIPAAm), were synthesized by coupling carboxylic end-capped PNIPAAm (PNIPAAm-COOH) to AHA through amide bond linkages. was prepared grafting adipic dihydrazide the HA backbone and PNIPAAm-COOH via a facile thermo-radical polymerization technique NIPAAm using 4,4′-azobis(4-cyanovaleric acid) as an initiator, respectively. The structure AHA-g-PNIPAAm determined 1H NMR. Two copolymers with different weight ratios on applicability injectable hydrogels characterized. lower critical solution temperature (LCST) in PBS measured ∼30 °C rheological analysis, regardless degrees. Enzymatic resistance 28% 53% 100 U/mL hyaluronidase/PBS at 37 °C 12.3% 37.6% over 28 days, Equilibrium swelling 21.5, significantly decreased 13.3 37 °C. Results from SEM observations confirm porous 3D hydrogel interconnected pores after freeze-drying and the pore diameter depends PNIPAAm. Encapsulation human adipose-derived stem cells (ASCs) within showed noncytotoxic preserved viability entrapped cells. preliminary vivo study demonstrated usefulness for adipose tissue engineering. This newly described thermoresponsive attractive properties serve cell or pharmaceutical delivery vehicles variety engineering applications.