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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Amyloid Peptide Mixtures: Self-Assembly, Hydrogelation, Nematic Ordering, and Catalysts in Aldol Reactions

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Author(s):
Pelin, Juliane N. B. D. [1, 2] ; Gerbelli, Barbara B. [1] ; Edwards-Gayle, Charlotte J. C. [2] ; Aguilar, Andrea M. [3] ; Castelletto, Valeria [2] ; Hamley, Ian W. [2] ; Alves, Wendel A. [1]
Total Authors: 7
Affiliation:
[1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210580 Santo Andre, SP - Brazil
[2] Univ Reading, Dept Chem, Reading RG6 6AD, Berks - England
[3] Univ Fed Sao Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-09972270 Diadema - Brazil
Total Affiliations: 3
Document type: Journal article
Source: Langmuir; v. 36, n. 11, p. 2767-2774, MAR 24 2020.
Web of Science Citations: 0
Abstract

Morphological, spectroscopic, and scattering studies of the self-assembly and aggregation of mixtures of {[}RF] 4 and P{[}RF] 4 peptides (where R = arginine; F = phenylalanine; P = proline), in solution and as hydrogels, were performed to obtain information about polymorphism. CD data confirmed a beta-sheet secondary structure in aqueous solution, and TEM images revealed nanofibers with diameters of similar to 10 nm and micrometer lengths. SAXS curves were fitted using a mass fractal-component and a long cylinder shell form factor for the liquid samples, and only a long cylinder shell form factor for the gels. Increasing the P{[}RF](4) content in the systems leads to a reduction in cylinder radius and core scattering density, suggesting an increase in packing of the peptide molecules; however, the opposite effect is observed for the gels, where the scattering density is higher in the shell for the systems containing higher P{[}RF](4) content. These compounds show potential as catalysts in the asymmetric aldol reactions, with cyclohexanone and p-nitrobenzaldehyde in aqueous media. A moderate conversion (36.9%) and a good stereoselectivity (69:31) were observed for the system containing only {[}RF](4). With increasing P{[}RF](4) content, a considerable decrease of the conversion was observed, suggesting differences in the self-assembly and packing factor. Rheological measurements were performed to determine the shear moduli for the soft gels. (AU)

FAPESP's process: 14/50867-3 - INCT 2014: National Institute of Science and Technology in Bioanalysis
Grantee:Lauro Tatsuo Kubota
Support Opportunities: Research Projects - Thematic Grants
FAPESP's process: 17/02317-2 - Interfaces in materials: electronic, magnetic, structural and transport properties
Grantee:Adalberto Fazzio
Support Opportunities: Research Projects - Thematic Grants
FAPESP's process: 18/05888-3 - Biosensors based on amphiphilic peptides for detection and diagnosis of diseases
Grantee:Barbara Bianca Gerbelli
Support Opportunities: Scholarships in Brazil - Post-Doctoral
FAPESP's process: 18/12535-0 - Self-organization of hierarchical structures of peptide in solution in presence of metallic nanoparticles
Grantee:Juliane Nogueira Batista Dias Pelin
Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
FAPESP's process: 15/20446-9 - Study of auto-organization in solution of hierarchical structures of peptide in presence of metallic nanoparticles
Grantee:Juliane Nogueira Batista Dias Pelin
Support Opportunities: Scholarships in Brazil - Doctorate (Direct)