Abstracts Book - IMRC 2018

• SB2-O014 Invited Talk
BIO-INSPIRED STRUCTURES AND APPROACHES TO ELUCIDATE
CELL-SURFACE INTERACTIONS
Fabio Variola 1
1 University of Ottawa, Department of Mechanical Engineering, Canada.
In the quest for the next generation of functional biomaterials, researchers have
sought inspiration from nature by developing better performing bio-derived
materials (e.g. collagen, keratin, chitosan), reproducing naturally occurring
micro and nanostructures (e.g. gecko feet fibrils, nanoporosity of collagenapatite
interfaces in bone) and devising strategies that mimic naturally occurring
phenomena (e.g. mussel attachment). In this context, our team has joined these
efforts to employ bio-inspired structures and approaches in biomaterials
research, aiming at creating platforms and interface to understand and control
cellular events. In particular, we successfully reproduced a bioactive
nanoporosity on titanium, the gold standard in medicine, by simple
chemical (i.e. oxidative nanopatterning) and electrochemical (i.e. anodization)
methods, capable of positively affecting cell activity. Noteworthily, anodization
permitted not only to create semiordered nanotubular surfaces which can be
tuned in terms of diameter and spacing, but also a nanometric 3- dimensional
hierarchical surface that mimics the silicified cell wall (frustule) of diatoms.
This ultimately demonstrates that a simple anodization process can create
complex periodic structures which, to date, have only been made by more
complex techniques (e.g. two photon lithography, atomic layer deposition).
These surfaces were exploited to close in on the mechanisms that control how
human mesenchymal stem cells respond to nanotopographical surfaces, a
fundamental aspect in expanding the present knowledge of cell-surface
phenomena. In particular, our team focuses on the correlation between the
geometrical arrangement of nanoscale features to specific cellular functions,
and on the evaluation the effects of a vertical nanotopographical gradient by
exploiting such bioinspired surface. Moreover, we are currently working on
biologically inspired adhesive interfaces because of their potentially beneficial
applications in medicine, technology and industry not only for their capacity to
act as intermediate linkers to immobilize bioactive agents onto surfaces, but
also for their ability to direct influence cell behavior. In particular, we focused
on understanding the effects on cells of poly(dopamine), an adhesive polymer
derived from mussels, as a multifunctional layer for supporting the activity of
osteoblastic and human mesenchymal stem cells. In parallel, our team has also