Conjugation of Arg-Gly-Asp sequence into thermo-reversible gel as an extracellular matrix for 3T3-L1 fibroblast cell culture

High molecular weight N-isopropylacrylamide copolymers with small amounts o f acrylic acid (typically 2-5 mol% in feed) were synthesized by free radica l polymerization in benzene and then conjugated with adhesion molecules of Gly-Arg-Gly-Asp-Ser (GRGDS) peptides. Aqueous polymer solutions (5, 6, 8 an d 10% w/v) in culture medium (pH 7.4, ionic strength; 0.15 M) with 3T3-L1 f ibroblast cells were mixed and poured in Millicells, which supported the ge l formation without a significant gel induction time at 36 degrees C (gelat ion temperature). The initially formed gel was translucent and became more opaque as the temperature increased. The interaction between fibroblast cel ls and an artificial matrix of GRGDS containing p(NiPAAm-co-AAc) copolymer gel resulted in effective cell attachment, proliferation and growth. This s tudy supported that specific attachment is the result of the interaction be tween the integrin families on the fibroblast and the RGD sequence on the p (NiPAAm-co-AAc) copolymer gel.