Poly(ethylene glycol)s With a Single Cinnamaldehyde Acetal Unit for Fabricating Acid-Degradable Hydrogel

Xinyue Zhao; Pengfei Shan; Haiwei Liu; Daai Li; Peihan Cai; Zhongyu Li; Zhihui Li

doi:10.3389/fchem.2020.00839

Poly(ethylene glycol)s With a Single Cinnamaldehyde Acetal Unit for Fabricating Acid-Degradable Hydrogel

Front Chem. 2020 Sep 15:8:839. doi: 10.3389/fchem.2020.00839. eCollection 2020.

Authors

Xinyue Zhao¹, Pengfei Shan^{1

2}, Haiwei Liu³, Daai Li^{1

2}, Peihan Cai², Zhongyu Li², Zhihui Li¹

Affiliations

¹ State Key Laboratory of Optometry & Vision Science, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.
² College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, China.
³ The Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.

Abstract

A synthetic route to prepare a poly(ethylene glycol) with a single cinnamaldehyde acetal unit in the polymer chain, was successfully established using a newly synthesized cinnamaldehyde acetal diethylene glycol (CADEG) as initiator. This HO-PEG(ca)-OH is non-toxic and would be degraded into a cinnamaldehyde and two PEG diols in acid environment. A whole polyethylene glycol based hydrogel was easily fabricated by thiol-ene "click" reaction in alkalescence aqueous solution using acrylate-PEG(ca)-acrylate and 4-arm PEG-SH as raw materials at room temperature. The gel time was dependent on the pH of the solution and its alkalinity can promote gel. The hydrogel can be degradable in acidic conditions and the stronger the acidity, the faster the degradation. This HO-PEG(ca)-OH also can be used in synthesis of cinnamaldehyde containing PEG derivatives, block copolymers or other acid degradable materials.

Keywords: acetal; acid-degradable; cinnamaldehyde; hydrogel; poly(ethylene glycol).