title: Nanocomposite gold-silk nanofibers.
abstract: Cell-biomaterial interactions can be controlled by modifying the surface chemistry or nanotopography of the material, to induce cell proliferation and differentiation if desired. Here we combine both approaches in forming silk nanofibers (SNFs) containing gold nanoparticles (AuNPs) and subsequently chemically modifying the fibers. Silk fibroin mixed with gold seed nanoparticles was electrospun to form SNFs doped with gold seed nanoparticles (SNF(seed)). Following gold reduction, there was a 2-fold increase in particle diameter confirmed by the appearance of a strong absorption peak at 525 nm. AuNPs were dispersed throughout the AuNP-doped silk nanofibers (SNFs(Au)). The Young's modulus of the SNFs(Au) was almost 70% higher than that of SNFs. SNFs(Au) were modified with the arginine-glycine-aspartic acid (RGD) peptide. Human mesenchymal stem cells that were cultured on RGD-modified SNF(Au) had a more than 2-fold larger cell area compared to the cells cultured on bare SNFs; SNF(Au) also increased cell size. This approach may be used to alter the cell-material interface in tissue engineering and other applications.
authors.affiliation: David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA.
authors.forename: Tzahi
authors.initials: T
authors.lastname: Cohen-Karni
authors.forename: Kyung Jae
authors.initials: KJ
authors.lastname: Jeong
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Tsui
authors.forename: Gally
authors.initials: G
authors.lastname: Reznor
authors.forename: Mirela
authors.initials: M
authors.lastname: Mustata
authors.forename: Meni
authors.initials: M
authors.lastname: Wanunu
authors.forename: Adam
authors.initials: A
authors.lastname: Graham
authors.forename: Carolyn
authors.initials: C
authors.lastname: Marks
authors.forename: David C
authors.initials: DC
authors.lastname: Bell
authors.forename: Robert
authors.initials: R
authors.lastname: Langer
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Kohane
mesh_terms: D048429:Cell Size; D002478:Cells, Cultured; D055119:Elastic Modulus; D006046:Gold; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology; D009842:Oligopeptides; D047011:Silk; D023822:Tissue Engineering
chemical_list: D009842:Oligopeptides; D047011:Silk; D006046:Gold; C047981:arginyl-glycyl-aspartic acid