title: Methods to determine the pressure dependence of the molecular order parameter in (bio)macromolecular fibres.
abstract: The experimental realization and an algorithm for analysing the pressure dependence of the molecular order parameter of specific structural moieties in (bio)macromolecular fibres are described. By employing a diamond anvil cell (DAC) the polarization-dependent IR-transmission and in parallel, using an integrated microscope, the macroscopic orientation of the fibres is determined. This enables one to separate between order and disorder at macroscopic and microscopic scales. Using the example of spider silk the pressure dependence of the molecular order parameter of alanine groups being located within nano-crystalline building blocks is deduced and found to decrease reversibly by 0.01 GPa(-1) when varying the external hydrostatic pressure between 0 and 3 GPa.
authors.affiliation: Universität Leipzig, Fakultät für Physik und Geowissenschaften, Institut für Experimentelle Physik I, Abteilung Molekülphysik, Linnéstraße 5, D-04103 Leipzig, Germany. anton@physik.uni-leipzig.de.
authors.forename: Arthur Markus
authors.initials: AM
authors.lastname: Anton
authors.forename: Christof
authors.initials: C
authors.lastname: Gutsche
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Kossack
authors.forename: Friedrich
authors.initials: F
authors.lastname: Kremer
mesh_terms: D000818:Animals; D018130:Diamond; D006874:Hydrostatic Pressure; D047011:Silk / Q000737:chemistry*; D013055:Spectrophotometry, Infrared / Q000295:instrumentation / Q000379:methods*; D013112:Spiders
chemical_list: D047011:Silk; D018130:Diamond