Schiff Base-Crosslinked Tetra-PEG-BSA Hydrogel: Design, Properties, and Multifunctional Functions

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Hydrogel network structures are critical for mechanical properties and applications in biomedical and industrial fields.
• Rational design of hydrogels is essential for optimizing performance.
• Existing hydrogels may have limitations in gelation speed, stability, and mechanical strength.

Purpose of the Study:

• To develop a novel Schiff base-crosslinked hydrogel using Tetra-armed polyethylene glycol with aldehyde end groups (Tetra-PEG-CHO) and bovine serum albumin (BSA).
• To characterize the gelation time, optical properties, swelling behavior, mechanical strength, and biocompatibility of the developed Tetra-PEG-BSA hydrogel.
• To compare the performance of the Tetra-PEG-BSA hydrogel against control hydrogels.

Main Methods:

• Schiff base crosslinking reaction between Tetra-PEG-CHO and BSA under alkaline conditions.
• Measurement of gelation time, optical transmittance, and swelling ratios.
• Assessment of structural integrity in denaturing environments (guanidine hydrochloride, SDS).
• Mechanical testing including strain at break, rupture stress, and energy dissipation.
• MTT cytotoxicity assays for biocompatibility evaluation.

Main Results:

• Tetra-PEG-BSA hydrogel exhibited rapid gelation (approx. 11 s), significantly faster than controls.
• Achieved high optical transmittance (92.92% at 600 nm) and superior swelling ratios.
• Maintained structural integrity in denaturing solutions.
• Demonstrated enhanced mechanical properties: high strain at break (84.12 ± 0.76%), rupture stress (28.64 ± 1.21 kPa), and energy dissipation (468.0 ± 34.9 kJ·m⁻³).
• MTT assays confirmed excellent biocompatibility with cell viability >80% at lower concentrations.

Conclusions:

• The developed Tetra-PEG-BSA hydrogel offers rapid gelation, excellent mechanical strength, and high stability.
• Its superior properties and biocompatibility make it a promising candidate for various biomedical applications.
• Potential applications include drug delivery, tissue engineering, and 3D printing.