The Power of SAXS: Exploration of the Magic World of

Bio- and Nanomaterials

Michael Rappolt

School of Food Science and NutritionFACULTY OF MATHEMATICS AND PHYSICAL SCIENCES

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-

e-

e-

e-Transmission

e- photoelectron

e-

e-

e-

e-

e-

e- e-

Absorption

e-

Fluorescence

Interaction of X-rays with Matter (cont.)

e-

e-

e-

e-

e-

e-

e-

e-

Scattering

Elastic Scattering: hν’ = hν (Thomson)

Inelastic Scattering: hν’ < hν (Compton)

e-

e-

e-

e-

e-

e-

e-

e-

Pair Production E = hν > 1 MeV*

e-

e+

*1 eV = 1.602 10-19 J

millimeter

What can we see?

micrometer

kera

tin

nanometer

?

The Austrian SAXS Beamline

light-source:Sincrotone Trieste

monochromator for 5.4, 8 and 16 keV

sample

X-ray pattern

toroidal mirror:focal spot size

1.2 x 0.6 mm2 (FWHM)

variable

sample

area

camera length: Up to 5 m

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

Rosalind Franklin's X-ray diffraction photograph of DNA, 1953

Diffuse scattering of water

Powder diffraction on lipid/water systems

Surface Diffraction

Solution Scattering: Diluted Systems

3

RqexpVpqI

2

g

2

p

2Guinier Approximation (qR<<1):

Scattering function of monodisperse spheres

4qP

.constqI Porod Approximation (qR>>1):VS

pP 2

X-ray

ki

kfq

I(q)

Fast Chemical Reactions in a Free Standing Jet

Na2CO3 + CaCl2 → CaCO3 + 2NaCl

Concentration of reagents: 50 mM

Free jet micromixer to study sub 100 s chemical and biological reactions

•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)

Shape Analysis of Proteins

M. Hammel, M. Kriechbaum, A. Gries, G.H. Kostner, P. Laggner & R. Prassl 2002 JMB 321, 85.

from crystal structure of b2GPI

shape reconstruction and rigid body refinement

crystalsolution

Discovery of the DNA-Structure

Rosalind Franklin's X-ray diffraction photograph of DNA

Watson and Crick in front of their DNA model, 1953

In-Situ Testing of Human Aortas: the Set-up

X-rays

Markers forvideo

extensometer

Total force recorded via load cells

Load protocols:– Uniaxial– Equibiaxial– Strip – biaxial

In-Situ Testing of Human Aortas: one Example

Time

Clamp position Force at clamp

In-Situ Testing of Human Aortas: Conclusion

Uniaxial

Biaxial

Strip biaxial

Uniaxial

Strip biaxial

λC

λL

Equi-biaxial

Uniaxial UniaxialStrip

biaxialStrip

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.

SAXD: Electron-Density of Lipid Liquid Crystals

SAXD

2 ·RWdPP

dL

electron density map

SAXD: Polymorphism of Lipid Liquid Crystals

H2

tem

pera

ture

I2

V2

La

additive

37 C

low

h

igh

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

Characterizing Quantum Dots with GISAXS

Simulation of a GISAXS pattern obtained for a 3nm thick deposit of Pd on MgO(100)@700K.

D

GISAXD: Membrane Fusion Caught in the Act

L. Yang, H.W. Huang, Science 297 (2002) 1877.

M. Rappolt, H. Amenitsch, S. Strancar, C.V. Teixeira, M. Kriechbaum, G. Pabst, M. Majerowicz & P. Laggner, P. (2004) Colloid Interface Sciences 111: 63-77.

Thank You!

Heinz Amenitsch, Barbara Sartori, Fernando Cacho-Nerin & Benedetta Marmiroli, Austrian SAXS Beamline Trieste, TU Graz

Sigrid Bernstorff

ELETTRA, Sincrotrone Trieste, Italy

My special thanks go to: