Work

Polypeptide‐Poly(Ethylene Glycol)‐Polypeptide Amphiphilic Triblock Copolymer Hydrogels With Tunable Stiffness via Varying Polypeptide Side‐Chain Moiety

Year: 2025

Type: article

Abstract: ABSTRACT This study investigates the hydrogelation behavior of amphiphilic triblock copolymers composed of a long poly(ethylene glycol) (PEG) chain as the hydrophilic central block and various aromatic polypeptides—poly(S‐benzyl‐ L ‐cysteine) (PBLC), poly(O‐benzyl‐ L ‐tyrosine) (PBLY), poly( L ‐phenylalanine) (PLF), poly(γ‐benzyl‐ L ‐glutamate) (PBLG), and poly(Z‐ L ‐lysine) (PZLL)—as hydrophobic terminal blocks. The results reveal that the long PEG chain, polypeptide chain length, and side‐chain functional group critically influence amphiphilic balance and non‐covalent interactions, which govern hydrogel formation and mechanical properties. Structural analysis identified intermolecular hydrogen bonding, π–π interactions on aromatic side chains, and PEG backbone entanglement as key factors stabilizing the hydrogel network. The PBLC‐PEG‐PBLC and PBLY‐PEG‐PBLY samples with a short polypeptide segment exhibited enhanced gel network stability and stiffness, evidenced by the crossover points of the moduli at the strain values higher than 300.0%. Among all the studied samples, PBLC 4.8 ‐PEG20000‐PBLC 4.8 and PLF 6 ‐PEG20000‐PLF 6 exhibited superior hydrogelation performance due to optimal hydrophilic/hydrophobic balance. Rheological studies demonstrated shear‐thinning behavior and recovery post‐deformation, highlighting suitability for injectable applications. However, higher stiffness was found to hinder smooth extrusion through needles. Additionally, the in vitro cytotoxicity proved their biocompatibility for normal cells. These findings underscore the potential of PEG‐based triblock copolymers with aromatic polypeptides for designing tunable hydrogels with tailored mechanical properties for biomedical applications.

Source: Journal of Polymer Science

DOI: 10.1002/pol.20250520

Authors: Thi Ha My Phan, Wei‐Cheng Huang, Jing‐Ting Lin, Yu‐Hsun Yang, Jeng‐Shiung Jan

Institution: National Cheng Kung University

Language: English

Topic: Hydrogels: synthesis, properties, applications

Subfield: Molecular Medicine

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Science and Technology Council, Ministry of Science and Technology

Awards: G1525713639, Anticancer Activities and Gut Microbiota Effect of Linear and Star-Shaped Polypeptides Grafted with Different Natural Aldehydes