Calcium phosphate is one of the most important biominerals.1,2 Templated or biomimetic calcium phosphate mineralization provides access to a large variety of calcium phosphate composites that could for instance be useful for bone repair. Most experiments on the formation of such composites involve the precipitation of a mineral phase from bulk aqueous solution. This process is, however, rather unrelated to true biological conditions because the effects of surfaces and interfaces are ignored.
The presentation will show how model surfaces, both at the solid-liquid3 and the liquid-air interface,4-7 affect calcium phosphate formation. A special emphasis is put on the effects of polycations, such as poly(2-dimethylethylamino methacrylate) (PDMAEMA), because polycations have been less extensively studied than polyanions and there is hence a lack of information on their role in calcium phosphate mineralization. This also applies to the effects of oligomeric compounds as mineralization templates.8 Our studies show that not only the type of surface (anionic vs. cationic) but also the charge of each polymer surface (charged vs. uncharged) and the architecture of the hydrophilic groups (dendritic vs. linear) strongly affect the outcome of the mineralization process. A preliminary hypothesis of how polycations may regulate calcium phosphate is also proposed9 and – time permitting – I will also present some recent data on how ionic liquids can be used to generate biotolerant composite materials.10
(1) Calcium Phosphates in Biological and Industrial Systems; Kluwer Academic Publishers: Norwell-Dordrecht, 1998.
(2) Handbook of Biomineralization; Wiley-VCH: Weinheim, 2007.
(3) Löbbicke, R.; Chanana, M.; Schlaad, H.; Pilz-Allen, C.; Günter, C.; Möhwald, H.; Taubert, A. Biomacromolecules 2011, 12, 3753.
(4) Casse, O.; Colombani, O.; Kita-Tokarczyk, K.; Müller, A. H. E.; Meier, W.; Taubert, A. Faraday Discuss. 2008, 139, 179.
(5) Junginger, M.; Bleek, K.; Kita-Tokarczyk, K.; Reiche, J.; Shkilnyy, A.; Schacher, F.; Müller, A. H. E.; Taubert Nanoscale 2010, 2, 2440.
(6) Junginger, M.; Kita-Tokarczyk, K.; Schuster, T.; Reiche, J.; Schacher, F. A.; Müller, A. H. E.; Cölfen, H.; Taubert, A. Macromol. Biosci. 2010, 10, 1084.
(7) Junginger, M.; Kübel, C.; Schacher, F. H.; Müller, A. H. E.; Taubert, A. RSC Adv. 2013, 3, 11301.
(8) Hentrich, D.; Junginger, M.; Bruns, M.; Börner, H. G.; Brandt, J.; Brezesinski, G.; Taubert, A. Cryst. Eng. Comm. 2015, DOI: 10.1039/C4CE02274B
(9) Shkilnyy, A.; Schöne, S.; Rumplasch, C.; Uhlmann, A.; Hedderich, A.; Taubert, A. Colloid Polym. Sci. 2011, 289, 881.
(10) Salama, A.; Neumann, M.; Günter, C.; Taubert, A. Beilstein. J. Nanotechnol. 2014, 5, 1553.