posted on 2014-05-14, 00:00authored bySrdjan
S. Aćimović, Maria A. Ortega, Vanesa Sanz, Johann Berthelot, Jose L. Garcia-Cordero, Jan Renger, Sebastian J. Maerkl, Mark P. Kreuzer, Romain Quidant
Label-free
biosensing based on metallic nanoparticles supporting
localized surface plasmon resonances (LSPR) has recently received
growing interest (Anker, J. N., et al. Nat. Mater.2008, 7, 442–453). Besides
its competitive sensitivity (Yonzon, C. R., et al. J. Am.
Chem. Soc.2004, 126, 12669–12676;
Svendendahl, M., et al. Nano Lett.2009, 9, 4428–4433) when compared to the surface
plasmon resonance (SPR) approach based on extended metal films, LSPR
biosensing features a high-end miniaturization potential and a significant
reduction of the interrogation device bulkiness, positioning itself
as a promising candidate for point-of-care diagnostic and field applications.
Here, we present the first, paralleled LSPR lab-on-a-chip realization
that goes well beyond the state-of-the-art, by uniting the latest
advances in plasmonics, nanofabrication, microfluidics, and surface
chemistry. Our system offers parallel, real-time inspection of 32
sensing sites distributed across 8 independent microfluidic channels
with very high reproducibility/repeatability. This enables us to test
various sensing strategies for the detection of biomolecules. In particular
we demonstrate the fast detection of relevant cancer biomarkers (human
alpha-feto-protein and prostate specific antigen) down to concentrations
of 500 pg/mL in a complex matrix consisting of 50% human serum.