Biomimetic formation of CaCO_1tn3 particles showing single and hierarchical structures [Elektronische Ressource] / vorgelegt von Alina-Elena Voinescu

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• Publié par: universitat_regensburg
• Publié le: 01 janvier 2008
• Nombre de lectures: 23
• Langue: English
• Poids de l'ouvrage: 6 Mo

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Biomimetic Formation of CaCO Particles 3
Showing Single and Hierarchical Structures







Dissertation
zur Erlangung des Grades
Doktor der Naturwissenschaften (Dr. rer. nat.)
der Naturwissenschaftlichen Fakultät IV
Chemie und Pharmazie
der Universität Regensburg




vorgelegt von
Alina-Elena Voinescu
Regensburg 2008












Promotionsgesucht eingereicht am: 08. April 2008
Promotionskolloquium am: 13. Mai 2008

Die Arbeit wurde angeleitet von Prof. Dr. Werner Kunz
Prüfungsausschuss:
Vorsitzender: Prof. em. Dr. Dr. h.c. Josef Barthel
1. Gutachter: Prof. Dr. Werner Kunz
2. Gutachter: Prof. Dr. Arno Pfitzner
3. Gutachter: Prof. Dr. Georg Schmeer












For Adrian Marinescu Acknowledgements
The present PhD project was undertaken at the Institute of Physical and Theoretical
Chemistry, University of Regensburg (Germany) and it is my pleasure to thank numerous
people, who became involved in many different ways.
First and foremost, I would like to thank my PhD supervisor, Prof. Werner Kunz, who
offered me this fascinating topic and provided me the best scientific support. I am
especially grateful to him for his constructive guidance during this time, which, combined
with his stimulating participation, kept me motivated and always enthusiastic.
Sincere thanks go to Dr. Didier Touraud, who although initially not a fan of this project, he
gave me all his guidance, support, encouragement and created an excellent base for a
successful collaboration. He offered me always an advice when things got complicated.
Particular thanks are addressed to Prof. Stephen T. Hyde and Prof. Barry W. Ninham for
having welcomed me warmly at the Research School of Physical Sciences and
Engineering, Australian National University (ANU) and for giving me the opportunity to
work at ANUEMU for three months. I would also like to thank them for their continuous
interest in my studies and for the introduction in the biomorphs science.
I am indebted to Prof. Arno Pfitzner and part of his team (Irina Anusca, Alois Lecker, and
Ulrike Schiessl) for their excellent collaboration and contribution in the field of
crystallography.
I extend many thanks to Dr. Michael Faatz and Prof. Gerhard Wegner, Max Planck
Institute (Mainz, Germany) for the helpful discussions concerning the formation of ACC. I
acknowledge also Dr. Joel Gautron, INRA (Tours, France) for his comments and advices
regarding the biological part of the Chapter 4. I thank Prof. Yves Bouligand, University of
Angers (France) for his comments regarding the morphogenesis of ‘coralline’ silica-
calcium carbonate.
I am grateful to Dr. Rainer Müller, University of Regensburg (Germany) and Dr. Ann-
Kristin Larsson, ANU (Australia) for the competent initiation in infrared and scanning
electron microscope analyses, respectively. I also thank Priv. -Doz. Dr. Lorenz Kienle
(Max Planck Institute, Stuttgart, Germany), Dr. Thomas Burgemeister, Josef Kiermaier,
31W. Krutina and Björn Bartel, for performing HRTEM, P NMR, ES-MS, elemental and
EDX analyses, respectively.
Special thanks go to my lab mates, Barbara Widera and Sabine Raith, for their constant
support and to my friends, Nina Vlachy, Jeremy Drapeau, Angelika Klaus, Viorica and
Sigfried Binder, Mioara and Alexandru Campeanu, and Gerda and Lüdwig Heitzer for the
wonderful time I had with them and for helping me whenever I needed it.
Very warm thanks are reserved to all professors and colleagues from the institute, who
created an ideal collaborative working atmosphere, important for me during the last years.
Finally, my deepest gratitude to my parents, Petrica and Elena, my brother, Marian, and
my best friends, Anca Tig and Alin Maftei, for their never-ending support. Table of Contents
Chapter 1 − Introduction ...............................................................1
Chapter 2 − Theoretical Background............................................5
2.1. Biomineralization ................................................................................................... 5
2.2. Calcium Carbonate Mineralization ...................................................................... 7
2.2.1. The Ions Involved.................................................................................................. 7
2.2.2. Classical Picture of Crystal Formation................................................................ 10
2.2.2.1. Nucleation......................................................................................................... 11
2.2.2.2. Crystal Growth ................................................................................................. 12
2.2.3. Calcium Carbonate Polymorphs.......................................................................... 14
2.2.3.1. Brief Depiction of Polymorphs ........................................................................ 14
2.2.3.2. General Pathways of the Crystallization Process ............................................. 16
2.2.3.3. Morphology and Polymorphs Selectivity Control in CaCO Mineralization... 18 3
2.3. Properties of Egg White Lysozyme and Casein Proteins.................................. 26
2.3.1. Egg White Lyzozyme .......................................................................................... 26
2.3.2. Casein Proteins .................................................................................................... 27
2.4. Biomorphs ............................................................................................................. 29
2.5. References 34
Chapter 3 − Techniques................................................................43
3.1. pH Measurements................................................................................................. 43
3.2. Dynamic Light Scattering.................................................................................... 43
3.3. Microscopic Techniques....................................................................................... 45
3.3.1. Optical Microscopy ............................................................................................. 45
3.3.2. Electron Microscopy............................................................................................ 46
3.3.2.1. Scanning Electron Microscope......................................................................... 47
3.3.2.2. Transmission Electron Microscope .................................................................. 48
3.4. Spectroscopic Techniques 49
3.4.1. Infrared Spectroscopy.......................................................................................... 50
3.4.2. Ultraviolet and Visible Spectroscopy 52
3.4.3. Nuclear Magnetic Resonance Spectroscopy ....................................................... 52
3.4.4. Mass Spectrometry .............................................................................................. 54
3.4.5. X-ray Diffraction ................................................................................................. 55
3.5. Chemical Composition ......................................................................................... 56
3.5.1. Energy Dispersive X-ray ..................................................................................... 56
3.5.2. CHNOS Elemental Analysis ............................................................................... 57
3.6. References ............................................................................................................. 57
Chapter 4 − The Formation of CaCO Single-Crystal Particles 3
Starting from Lysozyme Sols .......................................................59
4.1. Introduction .......................................................................................................... 59 Table of Contents II
4.2. Experimental Section ............................................................................................61
4.2.1. Materials Preparation ...........................................................................................61
4.2.2. Analytical Methods ..............................................................................................62
4.2.2.1 Particle Characterisation ....................................................................................62
4.2.2.2 Techniques Used to Study the Lysozyme-Calcium Interaction.........................63
4.3. Results and Discussion..........................................................................................63
4.3.1. Influence of Lysozyme on the Metastable Form of CaCO .................................63 3
4.3.2. Ageing of the Ly−ACC Particles .........................................................................67
4.3.2.1. Ly−ACC Nucleation, Lifetime and its Transformation to the Calcite Phase
during the first Hour after Reactant Mixing...................................................................67
4.3.2.2. The Amorphous Precipitate left in Contact with Mother Liquor for 24 h ........69