Injectable and thermosensitive poly(2-ethyl-2-oxazoline)-poly(L-alanine) hydrogel with enhanced mechanical
Zixuan Wang1, Xin Wang1, Zhiyong Chen1
1State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Shanghai Stomatological Hospital & School of Stomatology, Fudan University, Shanghai, 200438, China.
Acta Biomaterialia
|July 29, 2026
Summary
Researchers developed a new injectable thermosensitive hydrogel using poly(2-ethyl-2-oxazoline)-poly(L-alanine) (PEOz-PAla) copolymers. This advanced biomaterial offers enhanced mechanical strength and prolonged in vivo persistence for drug delivery and tissue engineering.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Thermosensitive hydrogels are promising injectable biomaterials.
- Conventional hydrogels face challenges with mechanical strength and in vivo duration.
- There is a need for improved hydrogel platforms for biomedical applications.
Purpose of the Study:
- To synthesize and characterize novel poly(2-ethyl-2-oxazoline)-poly(L-alanine) (PEOz-PAla) copolymers.
- To develop an injectable thermosensitive hydrogel with enhanced mechanical properties and in vivo stability.
- To establish a structure-property relationship for PEOz-PAla thermogelling polymers.
Main Methods:
- Amphiphilic PEOz-PAla copolymers were synthesized.
- Hydrogel properties (sol-gel transition, mechanical strength) were tuned by controlling block ratio and polymer concentration.
- Gelation mechanism was studied using multi-technique analyses.
- In vitro cytocompatibility and in vivo histological assessments were performed.
- Drug release kinetics were monitored using real-time fluorescence tracking.
Main Results:
- The PEOz-PAla hydrogel exhibited thermally induced micelle aggregation and utilized β-sheet-rich PAla domains for mechanical enhancement.
- The hydrogel demonstrated good storage stability and biocompatibility.
- In vivo degradation was gradual over 100 days at the subcutaneous injection site.
- Sustained release of macromolecular drugs was achieved for over 35 days.
Conclusions:
- The developed PEOz-PAla hydrogel offers superior mechanical properties and in vivo retention compared to existing thermosensitive hydrogels.
- This hydrogel platform is suitable for sustained drug delivery and tissue engineering.
- The study provides a design strategy for novel thermogelling polymers.
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