Direct Synthesis of Aliphatic Polyesters with Pendant Hydroxyl Groups from Bio-Renewable Monomers: A Reactive Precursor for Functionalized Biomaterials.

Introducing desired functionalities into biomaterials is an effective way to obtain functionalized biomaterials. A versatile platform with the possibility of postsynthesis functionalization is highly desired but challenging in biomedical engineering. In this work, linear aliphatic polyesters with pendant hydroxyl (PEOH) groups were directly synthesized using renewable malic acid/tartaric acid as raw materials under mild conditions through the polyesterification reaction promoted by 1,1,3,3-tetramethylguanidine (TMG). The hydroxyl groups on PEOH provide an active stepping stone for the fabrication of demanded functionalized polyesters. We demonstrated the possibility of the PEOH as a reactive precursor for functional group transformation, coupling of bioactive molecules, and formation of crosslinking networks. Moreover, a theranostic nanoplatform (mPEG-b-(P7-asp&TPV)-b-mPEG NPs) was synthesized using PEOH as a reactive stepping stone by the programmable combination of the above functionalization methods. Overall, these hydroxyl-containing polyesters have great potential in biological applications.