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Abstract Covalent attachment of thiols to the tyrosine residues of silk fibroin is accomplished with a high degree of functionalization through the reaction of a pyridyldithiol‐containing N‐hydroxysuccinimidal‐ester and an amino‐tyrosine silk intermediate. The extent of thiol modification is characterized by1H NMR and UV–vis spectroscopy. Further modification of the thiol groups is probed by reacting with an iodoacetamide‐containing small molecule resulting in a novel fluorescent silk derivative. Last, the ability of the thiolated silk to form hydrogels in situ is investigated.
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Chemical Modification of Silk Proteins via Palladium‐Mediated Suzuki−Miyaura Reactions
Abstract Suzuki−Miyaura cross‐coupling reactions are used to modify the tyrosine residues onBombyx morisilkworm silk proteins using a water‐soluble palladium catalyst. First, model reactions using tyrosine derivatives are screened to determine optimal reaction conditions. For these reactions, a variety of aryl boronic acids, solvents, buffers, and temperature ranges are explored. Qualitative information on the reaction progress is collected via high‐performance liquid chromatography (HPLC), mass spectrometry (MS), and nuclear magnetic resonance (NMR). Optimized reactions are then applied to silk proteins. It is demonstrated the ability to modify silk fibroin in solution by first iodinating the tyrosine residues on the protein, and then carrying out Suzuki‐Miyaura reactions with a variety of boronic acid derivatives. Modification of silk is confirmed with NMR, ion‐exchange chromatography (IEC), UV‐vis, and infrared spectroscopy (IR).
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- Award ID(s):
- 1807878
- PAR ID:
- 10468909
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/macp.202300307
