Enzymatically Cross-Linked Hydrogel Beads Based on a Novel Poly(aspartamide) Derivative

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Hydrogel beads and in situ hydrogels are increasingly utilized in biomedicine.
• Poly(aspartamide) derivatives offer potential for advanced hydrogel applications.

Purpose of the Study:

• To synthesize and characterize a novel phenolic hydroxyl-functionalized poly(aspartamide) derivative, PHEA-HP.
• To evaluate the potential of PHEA-HP for enzyme-catalyzed cross-linking to form in situ hydrogels and hydrogel beads.
• To assess the biocompatibility and tunable properties of the developed hydrogels.

Main Methods:

• Synthesis of PHEA-HP by introducing 3-(4-hydroxyphenyl) propionic acid (HP) into poly(α,β-[N-(2-hydroxyethyl)-D,L-aspartamide]) (PHEA).
• Characterization using FT-IR, UV, and 1H NMR.
• In vitro cytotoxicity (L929 cells) and hemolysis assays for biocompatibility.
• Rheological measurements and vial-tilting method for gelation properties.
• Preparation of hydrogel beads using coaxial needle and syringe pumps.

Main Results:

• PHEA-HP exhibited no cytotoxicity (viability > 90%) and good blood compatibility.
• Formation of PHEA-HP-based in situ hydrogels confirmed by rheology (G' ~ 10^4 Pa).
• Gelation time was tunable from 5-260 s by adjusting H2O2 and HRP concentrations.
• Hydrogel beads of varying diameters were successfully prepared, with size influenced by outer phase flow rate.

Conclusions:

• PHEA-HP is a safe and promising poly(aspartamide) derivative for hydrogel applications.
• The material allows for tunable gelation kinetics, suitable for in situ formation.
• PHEA-HP can be used to fabricate hydrogel beads with controlled dimensions for biomedical uses.