@article {19827, title = {Development of a novel localized surface plasmon resonance (LSPR) biosensor for relevant protein biomarker detection at point-of-care (POC) }, journal = {TERMSTEM}, year = {2017}, month = {2017-11-15 00:00:00}, address = {Porto}, abstract = {

LSPR (localized surface plasmon resonance) platforms offer label-free, sensitive, rapid, robust and versatile detection of biomolecules, being a desirable technology for Point of Care (POC) diagnostics.1 Gold nanoparticles are often used in these platforms for its biocompatibility and simple antibody immobilization.2 Nevertheless, this technology still presents challenges that need to be overcome, for POC integration, such as: improve the limit of detection (LOD) and the selectivity in complex media, develop multiplexing platforms for multiple detection of biomarkers as well as automated forms of fluid control.1

We present a novel LSPR technology constituted by thin films of TiO2 and CuO with embedded gold nanoparticles. The nanocomposite films were deposited by reactive DC magnetron sputtering and subjected to post-deposition thermal annealing up to 600 {\textordmasculine}C. The thickness of the thin films is lower than 100 nm, and the atomic concentrations of Au was close to 13 \% in both matrices. The manufacturing of these films is cost-effective and simple to up-scale, since the production process is straightforward and reproducible. It also allows the tuning of several parameters in order to optimize the LSPR signal and, therefore, improve detection mode sensitivity.3

The surface characterization of these nanocomposite films was performed by SEM and revealed Au nanoparticles with 50 nm diameter average covering about 18\% of thin film surface, for the Au/CuO thin films, and between 15 to 20 nm covering 8\% of thin film surface, for Au/TiO2 thin films. AFM analysis revealed a roughness of 2.64 nm for Au/TiO2 and 3.45 nm for Au/CuO. The size and surface exposure of Au nanoparticles is appropriated for effective antibody immobilization, which gives to these nanoplasmonic thin films a great potential for protein biomarker detection at POC settings.\ 

}, keywords = {AuTiO2 thin films, Biosensors, Localised Surface plasmon Ressonance, Point-of-Care Diagnostics}, author = {Barbosa, A. I. and Rebelo, R. and Meira, D. and Costa, D. and Rodrigues, M. and Borges, J. and Vaz, F. and Correlo, V. M. and Reis, R. L.} }