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Citation
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HERO ID
1050990
Reference Type
Journal Article
Title
Combinatorial Effects of Charge Characteristics and Hydrophobicity of Silk Fibroin on the Sorption and Release of Charged Dyes
Author(s)
Wongpanit, P; Rujiravanit, R
Year
2011
Is Peer Reviewed?
Yes
Journal
Journal of Biomaterials Science, Polymer Edition
ISSN:
0920-5063
EISSN:
1568-5624
Volume
23
Issue
9
Page Numbers
1199-1215
Language
English
PMID
21639994
DOI
10.1163/092050611X576972
Web of Science Id
WOS:000307445200005
Abstract
The present study was designed to examine the influence of the charge characteristics of silk fibroin on the sorption and release of charged dyes by varying the pH values of the sorption and release media as well as types of charged dyes. Negatively charged dyes (phenol red and chromotrope 2R) and positively charged dyes (crystal violet and indoine blue) were used as the model compounds. Silk fibroin films were prepared by using a solution casting technique. The prepared films were then treated with an aqueous methanol solution or annealed with water to control their conformation. The sorption behavior of the model compounds made by the methanol-treated and water-annealed silk fibroin films was investigated. Compared to the water-annealed silk fibroin films, a higher hydrophobicity of the methanol-treated silk fibroin films caused a higher sorption of the hydrophobic dyes. The dye molecules had a fairly high affinity to the silk fibroin film, even though the dye and the matrix possessed the same charge. However, in the presence of two charged groups in a single dye molecule, the electrostatic repulsion become more dominant. Stronger interaction was observed when the charges of the film and the dye were opposite. The results of dye sorption and release experiments showed that the degree of synergism or competition between electrostatic and hydrophobic interactions directly depended on the charges and chemical structure of the dye molecules and the environmental pH conditions of the existing silk fibroin film.
Keywords
Silk fibroin; electrostatic; hydrophobicity; release; partition coefficient
Tags
IRIS
•
Methanol (Non-Cancer)
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WOS
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