title: Keratin made micro-tubes: The paradoxical thermal behavior of cortex and cuticle.
abstract: Keratin micro-tubes were obtained by heating medullated keratin fibres to temperatures above 230°C under nitrogen atmosphere, when, as documented by microscopy, the cortex (the core of the fibre) melts from the medulla outwards, followed by pyrolysis of the material through the remaining solid cuticle (shell) layer. The resulted hollow tubes from fibres void of cortical material keep the external cuticle structure, as shown by AFM investigation, and the moisture sorption properties of the initial keratin fibre. Despite similar amino-acid compositions of cuticle and cortex the two morphological components differ significantly in their thermal behaviour, which appears to be a "cortex-cuticle thermal stability paradox".
authors.affiliation: DSM Resolve, Urmonderbaan 22, 6160 MD Geleen, The Netherlands.
authors.forename: Daniel
authors.initials: D
authors.lastname: Istrate
authors.affiliation: Institut Charles Sadron, CNRS, 23 rue du Loess, 67034 Strasbourg Cedex, France.
authors.forename: Meriem
authors.initials: M
authors.lastname: Er Rafik
authors.affiliation: KAO Germany GmbH, Pfungstaedterstr. 98-100, 64297 Darmstadt, Germany. Electronic address: crisan.popescu@kao.com.
authors.forename: Crisan
authors.initials: C
authors.lastname: Popescu
authors.affiliation: DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, 52056 Aachen, Germany.
authors.forename: Dan E
authors.initials: DE
authors.lastname: Demco
authors.affiliation: DWI-Leibniz-Institute for Interactive Materials, Forckenbeckstr. 50, 52056 Aachen, Germany.
authors.forename: Larisa
authors.initials: L
authors.lastname: Tsarkova
authors.affiliation: School of Materials, University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: Franz-Josef
authors.initials: FJ
authors.lastname: Wortmann
mesh_terms: D006197:Hair / Q000737:chemistry* / Q000648:ultrastructure; D006801:Humans; D007633:Keratins / Q000737:chemistry* / Q000648:ultrastructure; D009584:Nitrogen / Q000737:chemistry; D012867:Skin / Q000737:chemistry* / Q000648:ultrastructure; D013696:Temperature
chemical_list: D007633:Keratins; D009584:Nitrogen
keywords: Cuticle; Keratin fibre; Micro-tubes; Thermal stability