Evaluation of quaternization effect on chitosan-HAP composite for bone tissue engineering application

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Drug Delivery

Background:

• Chitosan's poor aqueous solubility limits its use in biomedical applications.
• Hydroxyapatite (HAP) is crucial for bone regeneration.
• Developing effective drug delivery systems for bone defects is essential.

Purpose of the Study:

• To improve chitosan solubility via quaternization for HAP composite fabrication.
• To evaluate quaternized chitosan-HAP composites as curcumin delivery vehicles for bone regeneration.
• To investigate the effect of quaternization degree on composite properties and bioactivity.

Main Methods:

• Chitosan was modified by quaternization to create low (LQC) and high (HQC) quaternized forms.
• In situ HAP growth was facilitated by modified chitosan at alkaline pH, forming LQC-HAP and HQC-HAP composites.
• Curcumin was loaded into the composites (LQC-HAP-C, HQC-HAP-C) and characterized.
• In vitro studies using MG-63 cells assessed biocompatibility, proliferation, and calcium mineralization.

Main Results:

• Quaternization significantly improved chitosan's aqueous solubility and facilitated HAP growth.
• Drug encapsulation efficiency increased 2.6-fold with quaternization.
• Curcumin-loaded composites demonstrated biocompatibility, enhanced cell proliferation, and a 2-fold increase in calcium mineralization.
• Mechanical strength slightly decreased, while drug release increased with quaternization.

Conclusions:

• Quaternized chitosan-HAP composites offer tailorable physicochemical properties for drug delivery.
• The degree of quaternization influences drug loading, release kinetics, and bioactivity.
• These composites show significant promise as advanced drug delivery systems for bone regeneration applications.