Zinc-substituted hydroxyapatite produced from calcium precursor derived from eggshells

• Published in: Ceramics international 2021-12, Vol.47 (23), p.33010-33019
• Main Authors: Mardziah, C.M., Ramesh, S., Tan, C.Y., Chandran, Hari, Sidhu, Amritpal, Krishnasamy, S., Purbolaksono, J.
• Format: Article
• Language: English
• Subjects: Eggshells; Hydroxyapatite; Morphological properties; Nano-particles; Phase analysis; Zinc-substituted HA
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2021.08.201

The availability of natural calcium derived from biowaste materials is an inexpensive alternative to commercial calcium reagents used to produce calcium phosphate bioceramics. This approach is more ecofriendly, cost effective and sustainable owing to its abundant availability. In this study, zinc-substituted hydroxyapatite (ZnHA-Es) was synthesised using calcium precursor derived from eggshells through precipitation method. Zn concentration was varied from 1 mol% to 5 mol% during the synthesis, and the derived powders were calcined at 700 °C in air atmosphere. XRD analysis revealed that ZnHA-Es powders were highly crystalline and comprised biphasic mixtures of HA as the major phase and β-tricalcium phosphate as the minor phase. FTIR examination indicated that all ZnHA-Es samples had a similar structure to pure HA as evidenced by the presence of frequency bands corresponding to phosphate, carbonate and hydroxyl functional groups. The disappearance of vibrational bands of carbonate groups became more apparent with increased Zn concentration. Microstructure analysis revealed that the derived nanostructured particles were spherical (approximately 40–100 nm in diameter) regardless of Zn substitution.