Injectable in situ forming glucose‐responsive dextran‐based hydrogels to deliver adipogenic factor for adipose tissue engineering

Abstract

An injectable and glucose-responsive hydrogel derived from dextran derivatives and lectin concanavalin A (ConA) was synthesized to deliver adipogenic factor for adipose tissue engineering. The gelation is attributed to the Schiff-base reaction cross-linking between aldehydic and aminated dextran. To enhance adipogenesis, the adipogenic factor of insulin was incorporated in the ConA immobilized hydrogels. The gelation time, compressive modulus, morphologies, weight loss, and swelling properties of the hydrogels were investigated. The ConA triggered a competitive displacement of dextran by glucose from the lectin receptor sites, and results in increasing swelling of the gel network. The swelling ratio (SR) of ConA immobilized hydrogel showed glucose dependent properties and linearly increased from 19.8 to 31.3 at 37 C in PBS at glucose concentrations between 0 and 1.0% (w/v). The in vitro release experiments showed that the insulin would be released from this dextran hydrogel into the local microenvironment in response to glucose, thus highlighting the potential of such a injectable and biodegradable hydrogel to be used as part of implantable scaffold to delivery adipogenic factor for adipose tissue engineering. V C 2012 Wiley Periodicals, Inc. J Appl Polym Sci 126: E180-E186, 2012

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