title: Surface properties of the skin of the pilot whale Globicephala melas.
abstract: On the skin surface of delphinids small biofoulers are challenged to high shear water flow and liquid-vapor interfaces of air-bubbles during jumping. This state of self-cleaning is supported by the even, nano-rough gel-coated epidermal surface of the skin. The present study focussed on the intercellular evolution of gel formation and the chemical composition of the gel smoothing the skin surface of the pilot whale, Globicephala melas, using X-ray photoelectron spectroscopy (XPS) in combination with cryo-scanning electron microscopy (CSM), and transmission electron microscopy (TEM). In the superficial layer of the epidermis, the stratum corneum, intercellular material was shown by electron optical methods to assemble from smaller into larger covalently cross-linked aggregates during the transit of the corneocytes towards the skin surface. XPS measurements showed that the surface of the skin and the intercellular gel included approximately the same amounts of polar groups (especially, free amines and amides) and non-polar groups, corresponding to the presence of lipid droplets dispersed within the jelly material. It was concluded from the results that the gel-coat of the skin surface is a chemically heterogeneous skin product. The advantages of chemically heterogeneous patches contributing to the ablation of traces of the biofouling process are discussed.
authors: Alfred Wegener Institute Foundation for Polar and Marine Research Bremerhaven, Am Handelshafen 12, D-27570 Bremerhaven, Germany. cbaum@awi-bremerhaven.de
authors: Christof
authors: C
authors: Baum
authors: Frank
authors: F
authors: Simon
authors: Wilfried
authors: W
authors: Meyer
authors: Lutz-Günther
authors: LG
authors: Fleischer
authors: Dietrich
authors: D
authors: Siebers
authors: Johannes
authors: J
authors: Kacza
authors: Johannes
authors: J
authors: Seeger
mesh_terms: D000818:Animals; D012634:Bodily Secretions / Q000737:chemistry*; D004289:Dolphins / Q000033:anatomy & histology* / Q000502:physiology; D008854:Microscopy, Electron; D009930:Organic Chemicals / Q000302:isolation & purification; D012867:Skin / Q000737:chemistry* / Q000648:ultrastructure*; D013057:Spectrum Analysis; D013499:Surface Properties
chemical_list: D009930:Organic Chemicals