Temperature-Responsive Graft Copolymer Hydrogels for Controlled Swelling and Drug Delivery

• Published in: Soft materials Vol. 11; no. 3; pp. 294 - 304
• Main Authors: Overstreet, Derek J., McLemore, Ryan Y., Doan, Brandon D., Farag, Amye, Vernon, Brent L.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01-07-2013
• Subjects: Drug delivery; Graft copolymer; N-isopropylacrylamide; Swelling; Temperature-responsive polymer
• ISSN: 1539-445X; 1539-4468
• DOI: 10.1080/1539445X.2011.640731

Temperature-responsive graft copolymers of N-isopropylacrylamide and Jeffamine® M-1000 acrylamide were synthesized to provide controlled swelling without introducing degradable moieties or increasing the LCST above body temperature. Jeffamine® M-1000 caused a small LCST increase (0.24-0.27°C/wt%) and a broader sol-gel transition. Twenty wt% copolymer gels (M
w
> 225 kDa) retained their initial volume after 42 days, while homopolymer gels shrank by more than 50%. Copolymer gels eluted <20% of ovalbumin over 6 days whereas homopolymer gels released >90% within 3 h. These results suggest that Jeffamine® M-1000 acrylamide is suitable for inclusion in N-isopropylacrylamide-based biomaterials to control swelling and drug release nearly independently of LCST.