David McDonogh M.Sc.
Raum 217, Gebäude 2501
Tel.: +49 511 / 762-2352
Titel der Dissertation
"Mechanisms and Additive Effects in the Early Stages of Calcium Phosphate Nucleation"
B.Sc. Chemistry – University of California, Berkeley
M.Sc. Chemistry – University Konstanz
Calcium Phosphates (CaP) have great importance in research both in biologically and industrially relevant roles. Bone and tooth material is composed of a mineralized matrix, with proteins and biopolymers mixed with CaP (mainly as apatite) and other trace elements.1 Much interest lies in developing CaP based materials for bone/tooth replacement, repair, implant coatings and cements.1 In industrial processes successful manipulation and/or removal of CaP can have implications for processing, purification, environmental safety and waste streams in applications ranging from sugar production to dairy farming.2-3
The nucleation of CaP plays a key role in its applications, however, the mechanism behind the function is not yet fully understood. The aim of this project is to develop a detailed mechanism for the nucleation of Calcium Phosphate. Emphasis is on describing the pH (speciation) influence on the pathway, description of intermediate or precursor stages and development of the final solid. The effect of additives on the nucleation pathway, and interaction with precursor states can also be explored; a wide range of additives small molecule, ions, polymers, proteins, etc. can be looked at in terms of biological and industrial relevance.
1. LeGeros, R. Z., Calcium Phosphate-Based Osteoinductive Materials. Chem. Rev. 2008, 108, 4742-4753.
2. Doherty, W. O. S., Improved Sugar Cane Juice Clarification by Understanding Calcium Oxide-Phosphate-Sucrose Systems. J. Agric. Food Chem. 2011, 59, 1829-1836.
3. Kezia, K.; Lee, J.; Zisu, B.; Chen, G. Q.; Gras, S. L.; Kentisch, S. E., Solubility of Calcium Phosphate in Concentrated Dairy Effluent Brines. J. Agric. Food Chem. 2017, 65, 4027-4034.