Micro- and nano-hydroxyapatite as active reinforcement for soft biocomposites

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Pectin-based hydrogels are versatile biomaterials.
• Hydroxyapatite (HA) can act as both a cross-linker and reinforcing agent.
• Controlling HA properties is key to tailoring hydrogel performance.

Purpose of the Study:

• To investigate the impact of different hydroxyapatite (HA) powders on pectin-based biocomposite hydrogels.
• To correlate HA characteristics with hydrogel properties like gelling time and mechanical strength.
• To determine the optimal HA type for specific hydrogel applications.

Main Methods:

• Internal gelation technique used for hydrogel synthesis.
• Utilized both commercially sourced and wet-chemically synthesized HA powders.
• Characterized HA powders (mineralogy, grain size, surface area, microstructure) and resulting hydrogels (gelling kinetics, rheology, stability).

Main Results:

• HA powder characteristics significantly influence biocomposite hydrogel properties.
• Grain size and specific surface area of HA correlate with gelling time and rheological behavior.
• Pectin pH affects ionic cross-linking and hydrogel thermal stability.

Conclusions:

• Micrometric HA is suitable for applications demanding fast gelling and enhanced mechanical properties.
• Synthesized nanometric HA is ideal for creating homogeneous hydrogels with tunable gelling kinetics.
• HA powder characteristics are critical for designing pectin-based biocomposites for targeted applications.