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Title: One-Pot Assembly of Drug-Eluting Silk Coatings with Applications for Nerve Regeneration
Clinical use of polymeric scaffolds for tissue engineering often suffers from their inability to promote strong cellular interactions. Functionalization with biomolecules may improve outcomes; however, current functionalization approaches using covalent chemistry or physical adsorption can lead to loss of biomolecule bioactivity. Here, we demonstrate a novel bottom-up approach for enhancing the bioactivity of poly(l-lactic acid) electrospun scaffolds though interfacial coassembly of protein payloads with silk fibroin into nanothin coatings. In our approach, protein payloads are first added into an aqueous solution with Bombyx mori-derived silk fibroin. Phosphate anions are then added to trigger coassembly of the payload and silk fibroin, as well as noncovalent formation of a payload-silk fibroin coating at poly(l-lactic) acid fiber surfaces. Importantly, the coassembly process results in homogeneous distribution of protein payloads, with the loading quantity depending on payload concentration in solution and coating time. This coassembly process yields greater loading capacity than physical adsorption methods, and the payloads can be released over time in physiologically relevant conditions. We also demonstrate that the coating coassembly process can incorporate nerve growth factor and that coassembled coatings lead to significantly more neurite extension than loading via adsorption in a rat dorsal root ganglia explant culture model.  more » « less
Award ID(s):
2045510
PAR ID:
10500560
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
ACS Biomaterials Science & Engineering
Volume:
10
Issue:
1
ISSN:
2373-9878
Page Range / eLocation ID:
482 to 496
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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