Researchers at the nanotechnology research centre imec
(Leuven, Belgium) have demonstrated biosensors based on novel nanostructure
geometries that increase the sensitivity and allow to detect extremely low concentrations
of specific disease markers. This paves the way to early diagnostics of for
example cancer by detecting low densities of cancer markers in human blood samples.
Functionalized nanoparticles can identify and measure extremely low concentrations
of specific molecules. They enable the realization of diagnostic systems with
increased sensitivity, specificity and reliability resulting in a better and
more cost-efficient healthcare. And, going one step further, functionalized
nanoparticles can help treat diseases, by destroying the diseased cells that
the nanoparticles bind to.
Imec aims at developing biosensor systems exploiting a phenomenon known as
localized surface plasmon resonance in noble metal (e.g. gold and silver) nanostructures.
The biosensors are based on optical detection of a change in spectral response
of the nanostructures upon binding a disease marker. The detection sensitivity
can be increased by changing the morphology and size of the noble metal nanostructures.
The biosensor system is cheap and easily extendable to multiparameter biosensing.
Imec today presents broken symmetry gold nanostructures that combine nanorings
with nanodiscs. Combining different nanostructures in close proximity allows
detailed engineering of the plasmon resonance of the nanostructures. More specifically,
imec targeted an optimization of both the width of the resonance peak and the
resonance shift upon binding of the disease marker. With respect to these parameters,
the new geometries clearly outperform the traditional nanospheres. Therefore,
they are better suited for practical use in sensitive biosensor systems.
“With our bio-nano research, we aim at playing an important role in
developing powerful healthcare diagnostics and therapy. We work on innovative
instruments to support the research into diseases and we look into portable
technologies that can diagnose diseases at an early stage. We want to help the
pharmaceutical and diagnostic industry with instruments to develop diagnostic
tests and therapies more efficiently;” said Prof. Liesbet Lagae, program
manager HUMAN++ on biomolecular interfacing technology.
Some of these results were achieved in collaboration with the Catholic University
of Leuven (Leuven, Belgium), Imperial College (London, UK) and Rice University
(Houston, Texas).