Mimicking Native Collagen Hierarchical Fibers: Understanding How Nano-fillers and External Stresses Effect Molecular and Fibril Ordering

Presenter: Marilyn Minus

Research Category: Engineering and Technology
Student Type: Graduate
Award Winner Category: Graduate Innovator Award

Collagen and collagen/nano-carbon fibers which exhibit multi-scale structure similar to native tendon were formed by a gel-spinning approach. For the collagen composite fibers, the rod-like nature of carbon nanotubes is exploited to understand its potential along with other rigid nano-carbons to promote ordered assembly of biological materials. This provides insight that may be applied toward other rigid nano-bodies which might be more suitable in synthetic bio-material assembly. For the synthetic formation of collagen materials, highly aligned collagen fibrils are necessary in order to replicate the native collagen structure. The morphology and dispersion quality of the nano-carbons was found to play a significant role in the overall collagen fibril alignment. X-ray scattering and microscopy analysis shows that the synthetic fibers exhibit molecular and fibrillar alignment, as well as D-banding formation consistent with native collagen. Beyond ordering, the nano-carbons used were also able to reinforce the collagen composite fibers. During post-processing or elongation of the fibers, the nano-carbons were capable of inducing higher levels of fibril alignment and packing as compared to control fibers. This work is the first to show direct evidence that nano-carbon fillers may promote collagen molecular and fibril alignment during both self-assembly and the application of external stress.