Melanin-containing films: growth from dopamine solutions versus layer-by-layer deposition.
Films formed by oxidation of dopamine are of interest for functionalisation of solid-liquid interfaces owing to their versatility. However, the ability to modulate the properties of such films, for example, permeability to ionic species and the absorption coefficient, is urgently needed. Indeed, melanin films produced by oxidation of dopamine absorb strongly over the whole UV/Vis part of the electromagnetic spectrum and are impermeable to anions even for a film thickness as low as a few nanometers. Herein we combine oxidation of dopamine to produce a solution containing dopamine-melanin particles and their alternating deposition with poly(diallyldimethylammonium chloride) to produce films which have nearly the same morphology as pure dopamine-melanin films but are less compact, more transparent and more permeable to ferrocyanide anions.
Bernsmann
Falk
F
Unité Mixte de Recherche 977, Institut National de la Santé et de la Recherche Médicale, 11 rue Humann, 67085 Strasbourg Cedex, France.
Ersen
Ovidiu
O
Voegel
Jean-Claude
JC
Jan
Edward
E
Kotov
Nicholas A
NA
Ball
Vincent
V
D000042:Absorption; D000498:Allyl Compounds / Q000737:chemistry; D004298:Dopamine / Q000737:chemistry*; D005295:Ferrocyanides / Q000737:chemistry; D008543:Melanins / Q000737:chemistry*; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
D000498:Allyl Compounds; D005295:Ferrocyanides; D008543:Melanins; D011108:Polymers; D000644:Quaternary Ammonium Compounds; C508190:diallyldimethylammonium chloride; C020354:hexacyanoferrate II; D004298:Dopamine