Temperature-responsive collagen–PNIPAAm conjugate: preparation and fibrillogenesis

Abstract

Collagen–polymer conjugates are being developed rapidly based on advancements in both polymer and protein science. The attachment of polymers to proteins can be achieved with the “grafting to” method or the “grafting from” method; the latter is more attractive. Although polymer-based collagen engineering provides an attractive strategy to regulate the native functions of collagen, there are still two important unresolved issues: the harsh modification conditions and the loss of fibrillogenesis property. Herein, a collagen–PNIPAAm conjugate (PCol) was prepared by the “grafting from” method to avoid harsh conditions. The amino groups of collagen were modified by a water-soluble NHS-functionalized ATRP initiator before in situ polymerization of NIPAAm on the collagen surface. On the other hand, the fibrillogenesis of PCol was realized by the induction of natural collagen, inspired by the xenogeneic collagen hybrid fibrils in organisms. Furthermore, the structure, fibrillogenesis, thermosensitivity, and biocompatibility of PCol were explored. This work may be useful in synthesizing optimized formulate collagen–polymer conjugates and helpful for the design of the novel collagen-based hybrid materials.