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Volume 9
Journal of Biotechnology & Biomaterials
ISSN: 2155-952X
Biomaterials 2019
February 25-26, 2019
Page 28
conference
series
.com
February 25-26, 2019 | London, UK
4
th
Annual Conference and Expo on
Biomaterials
Valentina Cauda, J Biotechnol Biomater 2019, Volume 9
DOI: 10.4172/2155-952X-C1-111
Hybrid smart nanocrystals and the shielding effect of phospholipid bilayer for biomedical application
Statement of the Problem:
Zinc oxide nanocrystals (ZnO NCs), thanks to their unique properties, are receiving much attention
for their use in nanomedicine, in particular for therapy against cancer. To be efficiently employed as diagnostic and therapeutic
(yet theranostic) tools, highly dispersed, stable and non-toxic nanoparticles are required. In the case of ZnO NCs, there is still a
lack of knowledge about cytotoxicity mechanisms and stability in the biological context, as well as immunological response and
hemocompatible features. We thus propose a novel approach to render stable, immune and hemocompatible ZnO NCs in various
biological media using artificial and natural phospholipidic bilayers.
Methodology & Theoretical Orientation:
We synthesized amino-functionalized ZnO NCs, then shielded with phospholipid
bilayers either from synthetic origin or natural biovesicles. We characterized their structural, morphological, physico-chemical
properties, focusing on the coupling mechanism between ZnO NCs and the lipid vesicles. The stability behavior of different hybrid
nanocrystals was evaluated, comparing their biodegradation profiles in different inorganic and biological media. The study aims to
investigate how the particle surface chemistry and charge could influence their aggregation/degradation in the different media and
interaction with cells. We actually proved their hemocompatibility in human plasma and their internalization into cancer cells and
related cytotoxicity mechanisms. A stimuli responsive activation by UV-light was investigated for inducing high mortality of cancer
cells based on the hybrid NCs.
Findings:
We demonstrated that pristine ZnO NCs strongly aggregate when suspended in both simulated and biological media,
showing small dissolution into potentially cytotoxic Zn-cations, also slightly affecting their crystalline structure. In contrast, high
colloidal stability and integrity was retained for hybrid lipid-shielded ZnO NCs in all media, accompanied by high biocompatibility,
efficient cell internalization and effective killing ability only upon stimuli-activation. These features render these hybrid ZnO NCs
ideal “Trojan horses” for further theranostic applications.
Figure 1: Scheme of the hybrid nanocrystal, as a Trojan horse showing higher bio- and hemocompatibility, long-term stability
in various biological and inorganic fluids, improved cell internalization with respect to pristine ZnO NCs. A stimuli responsive
behavior, guided by UV-light is also reported.
Valentina Cauda
Polytechnic University of Turin, Italy