Discipline: Biological Sciences
Subcategory: Materials Science
Vincent Hembrick-Holloman - Tuskegee University
Co-Author(s): Dr. Shaik Jeelani, Tuskegee University, Tuskegee, AL; Dr. Vijaya Rangari, Tuskegee University, Tuskegee, AL
Hydroxyapatite (HA) based biomaterials have been studied as a promising bioactive material for potential tissue engineering applications due to their favorable biological properties such as bioactivity, biocompatibility, and biodegradability. Every year, about 6 to 8 million tons of sea-shell waste is produced globally along with ~76 billion eggs consumed each year in the United States alone resulting in 1.2 million Kg of eggshell waste per year. In this study, we investigate the conversion of naturally occurring waste material, such as eggshells and seashells, into a valuable nanomaterial that can serve as a bioactive scaffold for bone and tooth regeneration. HA was synthesized using an energy efficient microwave-assisted wet chemical precipitation method by utilizing CaCO3 from egg and seashell as a precursor and H3PO4 as a source of phosphate ions. The HA was synthesized as follows: In the first step the CaCO3 powder was reacted with a HNO3 solution to produce a yellowish Ca(NO3)2 slurry. In the second step, diammonium hydrogen phosphate (DAHP) was synthesized by reacting NH4OH and H3PO4 in stoichiometric ratios. In the third step Ca(NO3)2 and DAHP were both dissolved separately in an aqueous solution and DAHP solution was added drop-by-drop into the Ca(NO3)2 solution. Finally the NH4OH was added to adjust the PH to 11. The reaction mixture was then exposed to microwave irradiation in an isothermal condition of 80o C for 15 min. The as prepared white precipitate was washed, several times with distilled water followed by ethanol. The final product was dried in a vacuum oven overnight and used for further analysis.Transmission electron microscopy, Scanning Electron Microscopy, X-ray Diffraction, and energy-dispersive X-ray spectroscopy studies confirmed crystalline HA particles in irregular shapes. The particle sizes measured are within the nanometer range, and displayed a chemical composition that matches very well with that of naturally occurring HA. Nanoscale hydroxyapatite particles were prepared from natural resources using an energy-efficient microwave-assisted wet chemical precipitation method. This serves as not only an inexpensive but sustainable, and environmentally friendly route to synthesize a valuable nanobiomaterial that can potentially be used in the fabrication of 3D printed dental tissue engineering scaffolds.ERN Abstract--2017.docx
Funder Acknowledgement(s): Alabama EPSCoR GRSP
Faculty Advisor: Dr. Vijaya Rangari, email@example.com
Role: All, I did my research solely in conjunction with help and feedback from my advisor.