A Single-Step Surface Modification of Electrospun Silica Nanofibers Using a Silica Binding Protein Fused with an RGD Motif for Enhanced PC12 Cell Growth and Differentiation
Wen Shuo Chen,
Ling Yu Guo,
Amien Mohamed Masroujeh,
Anna Morgan Augustine,
Cheng Kang Tsai,
Ting Yu Chin,
Yui Whei Chen-Yang,
Mong-Lin Yang
Affiliations
Wen Shuo Chen
Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Chung Li 32023, Taiwan
Ling Yu Guo
Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Chung Li 32023, Taiwan
Amien Mohamed Masroujeh
Department of Science, Concordia University Saint Paul, Saint Paul, MN 55104, USA
Anna Morgan Augustine
Department of Science, Concordia University Saint Paul, Saint Paul, MN 55104, USA
Cheng Kang Tsai
Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Chung Li 32023, Taiwan
Ting Yu Chin
Department of Bioscience Technology, Chung Yuan Christian University, Chung Li, 32023, Taiwan
Yui Whei Chen-Yang
Department of Chemistry, Center for Nanotechnology, Center for Biomedical Technology, Chung Yuan Christian University, Chung Li 32023, Taiwan
Mong-Lin Yang
Department of Science, Concordia University Saint Paul, Saint Paul, MN 55104, USA
In this study, a previously known high-affinity silica binding protein (SB) was genetically engineered to fuse with an integrin-binding peptide (RGD) to create a recombinant protein (SB-RGD). SB-RGD was successfully expressed in Escherichia coli and purified using silica beads through a simple and fast centrifugation method. A further functionality assay showed that SB-RGD bound to the silica surface with an extremely high affinity that required 2 M MgCl2 for elution. Through a single-step incubation, the purified SB-RGD proteins were noncovalently coated onto an electrospun silica nanofiber (SNF) substrate to fabricate the SNF-SB-RGD substrate. SNF-SB-RGD was characterized by a combination of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and immunostaining fluorescence microscopy. As PC12 cells were seeded onto the SNF-SB-RGD surface, significantly higher cell viability and longer neurite extensions were observed when compared to those on the control surfaces. These results indicated that SB-RGD could serve as a noncovalent coating biologic to support and promote neuron growth and differentiation on silica-based substrates for neuronal tissue engineering. It also provides proof of concept for the possibility to genetically engineer protein-based signaling molecules to noncovalently modify silica-based substrates as bioinspired material.