title: Superhydrophobic Surfaces Boost Fibril Self-Assembly of Amyloid β Peptides.
abstract: Amyloid β (Aβ) peptides are the main constituents of Alzheimer's amyloid plaques in the brain. Here we report how the unique microfluidic flows exerted by droplets sitting on superhydrophobic surfaces can influence the aggregation mechanisms of several Aβ fragments by boosting their fibril self-assembly. Aβ(25-35), Aβ(1-40), and Aβ(12-28) were dried both on flat hydrophilic surfaces (contact angle (CA) = 37.3°) and on nanostructured superhydrophobic ones (CA = 175.8°). By embedding nanoroughened surfaces on top of highly X-ray transparent Si3N4 membranes, it was possible to probe the solid residues by raster-scan synchrotron radiation X-ray microdiffraction (μXRD). As compared to residues obtained on flat Si3N4 membranes, a general enhancement of fibrillar material was detected for all Aβ fragments dried on superhydrophobic surfaces, with a particular emphasis on the shorter ones. Indeed, both Aβ(25-35) and Aβ(12-28) showed a marked crystalline cross-β phase with varying fiber textures. The homogeneous evaporation rate provided by these nanostructured supports, and the possibility to use transparent membranes, can open a wide range of in situ X-ray and spectroscopic characterizations of amyloidal peptides involved in neurodegenerative diseases and for the fabrication of amyloid-based nanodevices.
authors: Istituto Italiano di Tecnologia , Via Morego 30, Genova 16163, Italy.
authors: Angelo
authors: A
authors: Accardo
authors: Istituto Italiano di Tecnologia , Via Morego 30, Genova 16163, Italy.
authors: Victoria
authors: V
authors: Shalabaeva
authors: The European Synchrotron, CS40220 , 38043 Cedex 9 Grenoble, France.
authors: Emanuela
authors: E
authors: Di Cola
authors: The European Synchrotron, CS40220 , 38043 Cedex 9 Grenoble, France.|Department of Analytical Chemistry, Ghent University , Krijgslaan 281, Ghent 9000, Belgium.
authors: Manfred
authors: M
authors: Burghammer
authors: Istituto Italiano di Tecnologia , Via Morego 30, Genova 16163, Italy.
authors: Roman
authors: R
authors: Krahne
authors: The European Synchrotron, CS40220 , 38043 Cedex 9 Grenoble, France.
authors: Christian
authors: C
authors: Riekel
authors: Istituto Italiano di Tecnologia , Via Morego 30, Genova 16163, Italy.
authors: Silvia
authors: S
authors: Dante
mesh_terms: D000682:Amyloid / Q000737:chemistry*; D016229:Amyloid beta-Peptides / Q000737:chemistry*; D003890:Desiccation; D057927:Hydrophobic and Hydrophilic Interactions; D008567:Membranes, Artificial; D061848:Optical Imaging; D017655:Silicon Compounds / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D000682:Amyloid; D016229:Amyloid beta-Peptides; D008567:Membranes, Artificial; D017655:Silicon Compounds; C032734:silicon nitride
keywords: X-ray diffraction; convective flows; fibril self-assembly; superhydrophobic; synchrotron radiation; β-amyloid