Polymeric nanofibers have been widely used as scaffolds for tissue engineering, drug delivery, and filtration applications, among many others. A high throughput melt coextrusion technique and post-processing functionalization chemistry was recently developed to fabricate functional fibers with nanoscale dimensions. This manuscript expands upon the development of nanofiber modification chemistry by functionalizing fiber mats using a surface-initiated photo-induced electron transfer reversible addition–fragmentation chain transfer (PET-RAFT) polymerization technique. PET-RAFT allows for the fabrication of chemically diverse nanofiber systems initiated with light, preventing the need for high temperature thermal initiators. This manuscript describes the scope of monomers polymerizable via this technique on the surface of poly ε-caprolactone (PCL) nanofibers. The PET-RAFT modification chemistry is used to introduce block copolymers, provide multiple modifications using an orthogonal RAFT-ATRP system, induce spatial photopatterning and to establish cell-adhesive capabilities. The development of surface-initiated PET-RAFT adds an additional tool to a growing strategy for nanofiber functionalization.
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Low-Temperature Air Plasma Modification of Electrospun Soft Materials and Bio-interfaces
For several decades, plasma processing has been employed in the areas of food processing, manufacturing, and agriculture. Plasma processing has also been recognized as greatly beneficial in the field of tissue engineering for the modification of biomaterials. Polyethylene terephthalate (PET) has been employed as a vascular graft material but fails in small diameter applications. In this work, a multifaceted approach combining electrospinning to produce nano- and microscale fibers from PET blended with polybutylene terephthalate (PBT) added for flexibility and plasma modification for enhancing the surface chemistry is demonstrated to be an efficient approach to increase the biocompatibility as evidenced by enhanced fibroblast growth. The analysis of the surface chemistry shows an increase in oxygenated surface functionality, while the bulk analysis shows no significant changes. Thus, an efficient methodology for producing PET/PBT-based grafts that are easily modified with low-temperature plasma and show enhanced biocompatibility for vascular tissue engineering applications is reported.
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- Award ID(s):
- 1655280
- PAR ID:
- 10093491
- Date Published:
- Journal Name:
- TMS 2019 148th Annual Meeting & Exhibition Supplemental Proceedings
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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