Thermo-sensitive, injectable, and tissue adhesive sol–gel transition hyaluronic acid/pluronic composite hydrogels prepared from bio-inspired catechol-thiol reaction

TLDR

Hyaluronic acid hydrogels are widely pursued for tissue regeneration and drug delivery because of their biocompatibility and biodegradability. The study introduces a novel thermo‑sensitive, injectable, mussel‑inspired HA/Pluronic F127 composite hydrogel with tissue‑adhesive properties for biomedical use. By conjugating HA with dopamine and mixing it with thiol‑end‑capped Pluronic F127, the authors generate a lightly cross‑linked composite gel through a Michael‑type catechol‑thiol addition reaction. The resulting hydrogels display rapid, reversible temperature‑dependent sol‑gel transitions, can be injected as a sol at room temperature and solidify into a robust, tissue‑adhesive gel at body temperature, offering superior in‑vivo stability for drug and cell delivery.

Abstract

Hyaluronic acid (HA) hydrogels are widely pursued as tissue regenerative and drug delivery materials due to their excellent biocompatibility and biodegradability. Inspired by mussel adhesion, we report here a novel class of thermo-sensitive and injectable HA/Pluronic F127 composite tissue-adhesive hydrogels applicable for various biomedical applications. HA conjugated with dopamine (HA-DN) was mixed with thiol end-capped Pluronic F127 copolymer (Plu-SH) to produce a lightly cross-linked HA/Pluronic composite gel structure based on Michael-type catechol-thiol addition reaction. The HA/Pluronic hydrogels exhibited temperature-dependent sol–gel phase transition behaviors different from Pluronic hydrogels. Rheological studies showed that the sol–gel transitions were rapid and reversible in response to temperature. The HA/Pluronic hydrogels could be injected in vivo in a sol state at room temperature using a syringe, but immediately became a robust gel state at body temperature. The in situ formed hydrogels exhibited excellent tissue-adhesion properties with superior in vivo gel stability and are potentially useful for drug and cell delivery.