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pH- and Temperature-responsive Hydrogels Based on Tertiary Amine-modified Polypeptides for Stimuli-responsive Drug
Zhiqiang Lin1,2, Junfeng Ding1,2, Xuesi Chen1,2
1CAS Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, Jilin, P. R. China.
Chemistry, an Asian Journal
|March 1, 2023
Summary
New polypeptide hydrogels respond to pH and temperature. These biocompatible materials show potential for controlled drug delivery, releasing therapeutics faster in acidic environments.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Stimuli-responsive hydrogels are crucial for advanced therapeutic applications.
- Dual pH and temperature sensitivity offers precise control over material properties and drug release.
- Polypeptide-based hydrogels are gaining interest for their biocompatibility and biodegradability.
Purpose of the Study:
- To synthesize and characterize novel pH- and temperature-responsive hydrogels based on monomethoxy poly(ethylene glycol) (mPEG)-polypeptide block copolymers.
- To evaluate the stimuli-responsive behavior, including phase transitions and degradation profiles.
- To assess the in vitro drug release characteristics and in vivo biocompatibility of the developed hydrogels.
Main Methods:
- Synthesis of mPEG-polypeptide block copolymers (EEP-TAs) via ring-opening copolymerization and post-polymerization modification using click chemistry.
- Characterization of conformational changes (α-helix to β-sheet) in response to pH variations.
- Investigation of thermo-induced sol-gel phase transitions at different pH levels.
- In vitro degradation studies in mice subcutaneous layers and in vivo histocompatibility assessment.
- In vitro release studies of doxorubicin (DOX) from the hydrogels at varying pH conditions.
Main Results:
- The synthesized EEP-TAs demonstrated pH-dependent conformational changes (α-helix to β-sheet) between pH 4.0 and 7.4.
- Aqueous solutions of EEP-TAs exhibited pH-dependent, thermo-induced sol-gel transitions.
- The hydrogels showed rapid degradation within 3 weeks in vivo and good histocompatibility.
- DOX-loaded hydrogels displayed pH-responsive release, with faster release at acidic pH and sustained release at neutral pH.
Conclusions:
- The developed polypeptide hydrogels are responsive to both pH and temperature, offering tunable properties.
- These hydrogels exhibit favorable biocompatibility and biodegradability for in vivo applications.
- The pH-responsive drug release capability makes them promising candidates for controlled delivery of therapeutic agents.
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