001     22273
005     20240619092018.0
024 7 _ |2 pmid
|a pmid:22651227
024 7 _ |2 DOI
|a 10.1021/bm3006159
024 7 _ |2 WOS
|a WOS:000307422300020
024 7 _ |2 MLZ
|a doi:10.1021/bm3006159
037 _ _ |a PreJuSER-22273
041 _ _ |a eng
082 _ _ |a 540
084 _ _ |2 WoS
|a Biochemistry & Molecular Biology
084 _ _ |2 WoS
|a Chemistry, Organic
084 _ _ |2 WoS
|a Polymer Science
100 1 _ |0 P:(DE-HGF)0
|a Arzillo, M.
|b 0
245 _ _ |a Eumelanin Buildup on the Nanoscale: Aggregate Growth/Assembly and Visible Absorption Development in Biomimetic 5,6-Dihydroxyindole Polymerization
260 _ _ |a Columbus, Ohio
|b American Chemical Soc.
|c 2012
300 _ _ |a 2379 - 2390
336 7 _ |a Journal Article
|0 PUB:(DE-HGF)16
|2 PUB:(DE-HGF)
336 7 _ |a Output Types/Journal article
|2 DataCite
336 7 _ |a Journal Article
|0 0
|2 EndNote
336 7 _ |a ARTICLE
|2 BibTeX
336 7 _ |a JOURNAL_ARTICLE
|2 ORCID
336 7 _ |a article
|2 DRIVER
440 _ 0 |0 8221
|a Biomacromolecules
|v 13
|x 1525-7797
|y 8
500 _ _ |a This work was carried out in the frame of the EuMelaNet project (http://www.esper.org/eumelanet/). Financial support by MIUR, PRIN 2008 project, is gratefully acknowledged. We thank the Julich Centre for Neutron Science and the Rutherford Appleton Laboratory for provision of beam time. SANS experiments were supported by the European Commission, NMI3 contract RII3-CT-2003-505925.
520 _ _ |a Establishing structure-property relationships in the black insoluble eumelanins, the key determinants of human pigmentation and skin photoprotective system, is a considerable conceptual and experimental challenge in the current drive for elucidation of the biological roles of these biopolymers and their application as advanced materials for organoelectronics. Herein, we report a new breakthrough toward this goal by the first detailed investigation on the nanoscale level of the oxidative polymerization of 5,6-dihydroxyindole (DHI), a model process of eumelanin synthesis. On the basis of a combined use of spectrophotometry, dynamic light scattering (DLS), and small-angle neutron scattering (SANS) investigations, it was possible to unveil the dynamics of the aggregation process before precipitation, the key relationships with visible light absorption and the shape of fundamental aggregates. The results indicated a polymerization mechanism of the type: Polymer(n) + DHI(x) = Polymer(n+x), where DHI(x) indicates monomer, dimer, or low oligomers (x ≤ 5). During polymerization, visible absorption increases rapidly, reaching a plateau. Particle growth proceeds slowly, with formation of 2-D structures ~55 nm thick, until precipitation occurs, that is, when large aggregates with a maximum hydrodynamic radius (R(h)) of ~1200 nm are formed. Notably, markedly smaller R(h) values, up to ~110 nm, were determined in the presence of poly(vinyl alcohol) (PVA) that was shown to be an efficient aggregation-preventing agent for polymerizing DHI ensuring water solubilization. Finally, it is shown that DHI monomer can be efficiently and partially irreversibly depleted from aqueous solutions by the addition of eumelanin suspensions. This behavior is suggested to reflect oxidant-independent competing pathways of polymer synthesis and buildup via monomer conversion on the active aggregate surface contributing to particle growth. Besides filling crucial gaps in DHI polymerization, these results support the attractive hypothesis that eumelanins may behave as a peculiar example of living biopolymers. The potential of PVA as a powerful tool for solution chemistry-based investigations of eumelanin supramolecular organization and for technological manipulation purposes is underscored.
536 _ _ |0 G:(DE-Juel1)FUEK505
|2 G:(DE-HGF)
|x 0
|c FUEK505
|a BioSoft: Makromolekulare Systeme und biologische Informationsverarbeitung (FUEK505)
536 _ _ |0 G:(DE-HGF)POF2-544
|a 544 - In-house Research with PNI (POF2-544)
|c POF2-544
|f POF II
|x 1
588 _ _ |a Dataset connected to Web of Science, Pubmed
650 _ 7 |2 WoSType
|a J
650 2 7 |a Biology
|0 V:(DE-MLZ)SciArea-160
|2 V:(DE-HGF)
|x 0
650 1 7 |a Health and Life
|0 V:(DE-MLZ)GC-130-2016
|2 V:(DE-HGF)
|x 1
650 1 7 |a Health and Life
|0 V:(DE-MLZ)GC-130-1
|2 V:(DE-HGF)
|x 0
693 _ _ |0 EXP:(DE-MLZ)KWS2-20140101
|1 EXP:(DE-MLZ)FRMII-20140101
|5 EXP:(DE-MLZ)KWS2-20140101
|6 EXP:(DE-MLZ)NL3ao-20140101
|a Forschungs-Neutronenquelle Heinz Maier-Leibnitz
|e KWS-2: Small angle scattering diffractometer
|f NL3ao
|x 0
700 1 _ |0 P:(DE-HGF)0
|a Mangiapia, G.
|b 1
700 1 _ |0 P:(DE-HGF)0
|a Pezzella, A.
|b 2
700 1 _ |0 P:(DE-HGF)0
|a Heenan, R.K.
|b 3
700 1 _ |0 P:(DE-Juel1)VDB4342
|a Radulescu, A.
|b 4
|u FZJ
700 1 _ |0 P:(DE-HGF)0
|a Paduano, L.
|b 5
700 1 _ |0 P:(DE-HGF)0
|a d\\'Ischia, M.
|b 6
773 _ _ |0 PERI:(DE-600)2006291-6
|a 10.1021/bm3006159
|g Vol. 13, p. 2379 - 2390
|p 2379 - 2390
|q 13<2379 - 2390
|t Biomacromolecules
|v 13
|x 1525-7797
|y 2012
856 7 _ |u http://dx.doi.org/10.1021/bm3006159
909 C O |o oai:juser.fz-juelich.de:22273
|p VDB:MLZ
|p VDB
913 2 _ |0 G:(DE-HGF)POF3-623
|1 G:(DE-HGF)POF3-620
|2 G:(DE-HGF)POF3-600
|a DE-HGF
|b Forschungsbereich Materie
|l In-house research on the structure, dynamics and function of matter
|v Neutrons for Research on Condensed Matter
|x 0
913 1 _ |0 G:(DE-HGF)POF2-544
|1 G:(DE-HGF)POF2-540
|2 G:(DE-HGF)POF2-500
|a DE-HGF
|b Struktur der Materie
|v In-house Research with PNI
|x 1
|4 G:(DE-HGF)POF
|3 G:(DE-HGF)POF2
|l Forschung mit Photonen, Neutronen, Ionen
914 1 _ |y 2012
915 _ _ |0 StatID:(DE-HGF)0010
|2 StatID
|a JCR/ISI refereed
915 _ _ |0 StatID:(DE-HGF)0100
|2 StatID
|a JCR
915 _ _ |0 StatID:(DE-HGF)0110
|2 StatID
|a WoS
|b Science Citation Index
915 _ _ |0 StatID:(DE-HGF)0111
|2 StatID
|a WoS
|b Science Citation Index Expanded
915 _ _ |0 StatID:(DE-HGF)0150
|2 StatID
|a DBCoverage
|b Web of Science Core Collection
915 _ _ |0 StatID:(DE-HGF)0199
|2 StatID
|a DBCoverage
|b Thomson Reuters Master Journal List
915 _ _ |0 StatID:(DE-HGF)0200
|2 StatID
|a DBCoverage
|b SCOPUS
915 _ _ |0 StatID:(DE-HGF)0300
|2 StatID
|a DBCoverage
|b Medline
915 _ _ |0 StatID:(DE-HGF)0310
|2 StatID
|a DBCoverage
|b NCBI Molecular Biology Database
915 _ _ |0 StatID:(DE-HGF)1030
|2 StatID
|a DBCoverage
|b Current Contents - Life Sciences
915 _ _ |0 StatID:(DE-HGF)1050
|2 StatID
|a DBCoverage
|b BIOSIS Previews
915 _ _ |0 StatID:(DE-HGF)1150
|2 StatID
|a DBCoverage
|b Current Contents - Physical, Chemical and Earth Sciences
920 1 _ |0 I:(DE-Juel1)ICS-1-20110106
|g ICS
|k ICS-1
|l Neutronenstreuung
|x 0
920 1 _ |0 I:(DE-Juel1)JCNS-FRM-II-20110218
|k JCNS (München) ; Jülich Centre for Neutron Science JCNS (München) ; JCNS-FRM-II
|l JCNS-FRM-II
|x 1
920 1 _ |0 I:(DE-Juel1)JCNS-1-20110106
|g JCNS
|k JCNS-1
|l Neutronenstreuung
|x 2
970 _ _ |a VDB:(DE-Juel1)138695
980 _ _ |a VDB
980 _ _ |a ConvertedRecord
980 _ _ |a journal
980 _ _ |a I:(DE-Juel1)ICS-1-20110106
980 _ _ |a I:(DE-Juel1)JCNS-FRM-II-20110218
980 _ _ |a I:(DE-Juel1)JCNS-1-20110106
980 _ _ |a UNRESTRICTED
981 _ _ |a I:(DE-Juel1)IBI-8-20200312
981 _ _ |a I:(DE-Juel1)JCNS-1-20110106
981 _ _ |a I:(DE-Juel1)JCNS-FRM-II-20110218


LibraryCollectionCLSMajorCLSMinorLanguageAuthor
Marc 21