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School of Food Science and Nutrition Faculty of Mathematics and Physical Sciences. The Power of SAXS: Exploration of the Magic World of Bio- and Nanomaterials. Michael Rappolt. 2 . BSc Student Lecture: Physics with Introduction to Modern Physics
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School of Food Science and Nutrition Faculty of Mathematics and Physical Sciences The Power of SAXS: Exploration ofthe Magic World of Bio- and Nanomaterials Michael Rappolt 2. BSc Student Lecture: Physics with Introduction to Modern Physics 2nd of June 2014, Faculty of Electrical Engineering, University of Ljubljana
Interaction of X-rays with Matter e- e- e- e- Transmission e- e- e- e- e- e- e- e- photoelectron e- Absorption e- e- e- Fluorescence
Interaction of X-rays with Matter (cont.) e- e- e- e- Scattering e- Elastic Scattering: hν’ = hν (Thomson) e- e- e- Inelastic Scattering: hν’ < hν (Compton) e- e- Pair Production E = hν> 1 MeV* e- e- e- e- e- e- e- e+ *1 eV = 1.602 10-19 J
millimeter micrometer keratin nanometer What can we see? ?
The Austrian SAXS Beamline X-ray pattern camera length: Up to 5 m variable sample area monochromator for 5.4, 8 and 16 keV sample toroidal mirror: focal spot size 1.2 x 0.6 mm2 (FWHM) light-source: Sincrotone Trieste
Diffuse scattering of water Rosalind Franklin's X-ray diffraction photograph of DNA, 1953 Powder diffraction on lipid/water systems Surface Diffraction SAXS Methods • Solution Scattering: Formation of CaCO3; Proteins • Fiber-Diffraction: Discovery of DNA; Collagen • Small Angle X-ray Diffraction: Liquid Crystal Membranes • Grazing Incidence X-ray Scattering: Membrane Fusion; Quantum Dots
Guinier Approximation (qR<<1): Porod Approximation (qR>>1): Solution Scattering: Diluted Systems I(q) kf X-ray q ki Scattering function of monodisperse spheres
Na2CO3 + CaCl2→ CaCO3 + 2NaCl Concentration of reagents: 50 mM • Time of first accessible measurement 75 µs • The evolution of the chemical reaction is detected: volume fraction increasing Marmiroli, B., G. Grenci, F. Cacho-Nerin, B. Sartori, E. Ferrari, P. Laggner, L. Businaro and H. Amenitsch, Lab Chip, 9, 2063-2069 (2009) Fast Chemical Reactions in a Free Standing Jet Free jet micromixer to study sub 100 s chemical and biological reactions
Shape Analysis of Proteins from crystal structure of b2GPI shape reconstruction and rigid body refinement M. Hammel, M. Kriechbaum, A. Gries, G.H. Kostner, P. Laggner & R. Prassl 2002 JMB 321, 85. solution crystal
Discovery ofthe DNA-Structure Rosalind Franklin's X-ray diffraction photograph of DNA Watson and Crick in front of their DNA model, 1953
In-Situ Testingof Human Aortas: the Set-up Load protocols: Uniaxial Equibiaxial Strip – biaxial Total force recorded via load cells X-rays Markers forvideoextensometer
In-Situ Testingof Human Aortas: Conclusion Equi-biaxial Strip biaxial Strip biaxial Uniaxial Uniaxial λL Strip biaxial Schmid, F., Sommer, G., Rappolt, M., Schulze-Bauer, C.A.J., Regitnig, P., Holzapfel, G.A., Laggner, P., and Amenitsch, H. (2005) J. Synchrotron Rad. 12: 727-733. Biaxial Uniaxial Strip biaxial Uniaxial λC
SAXD: Electron-Densityof Lipid Liquid Crystals electron density map dPP 2 ·RW dL SAXD
SAXD: Polymorphismof Lipid Liquid Crystals temperature low high I2 37 C H2 V2 La additive Yaghmur, A., and Rappolt, M. (2011): Recent advances in the characterization of lipid-based nanocarriers. In: Nanotechnologies for Solubilization and Delivery in Foods, Cosmetics and Pharmaceuticals, Nissim Garti and Ididt Yuli-Amar (eds.), DEStech Publication Inc., Lancaster, pp. 187-208.
The GISAXS Set-Up Characterizing Quantum Dots with GISAXS Out of plane and in plane information
CharacterizingQuantum Dotswith GISAXS D Simulation of a GISAXS pattern obtained for a 3nm thick deposit of Pd on MgO(100)@700K.
GISAXD: Membrane Fusion Caught in theAct L. Yang, H.W. Huang, Science297 (2002) 1877. M. Rappolt, H. Amenitsch, S. Strancar, C.V. Teixeira, M. Kriechbaum, G. Pabst, M. Majerowicz & P. Laggner, P. (2004) Colloid Interface Sciences111: 63-77.
ThankYou! My special thanks go to: Heinz Amenitsch, Barbara Sartori, Fernando Cacho-Nerin & Benedetta Marmiroli, Austrian SAXS Beamline Trieste, TU Graz Sigrid Bernstorff ELETTRA, Sincrotrone Trieste, Italy