Nanoantennae to detect disease biomarkers

EU-funded scientists are developing novel optical nanoantennae exploiting the vibrational spectra of disease biomarkers for a sensitivity of two or three molecules.

Scientists are continuously identifying new proteins present in bodily fluids such as blood, plasma and saliva that are biomarkers of specific diseases and pathologies. Exploiting their full potential in early detection, diagnosis and treatment requires highly sensitive and specific sensors. EU-funded scientists working on the project NANOANTENNA are developing a novel optical biosensor targeted to detect even two or three biomarkers.

The system is based on the unique optical properties of functionalised metallic nanoparticles (NPs). The NPs have a bioreceptor molecule attached to them that binds the target biomarker with high specificity and affinity. The NPs then act as optical nanoantennae, enhancing light–matter interactions such that the spectroscopic vibrational signal of the proteins is detected through resonant excitation of the nanoantennae device. In other words, the metallic NPs are chosen to match their resonant frequencies to the vibrational frequencies of the molecules of interest, enabling them to increase the signal rather than dampen it.

The first step is thus determining the spectral signal of the four biomarker proteins of interest. Scientists are currently finishing experiments to obtain a complete record of the vibrational spectra of the proteins. In the end, the two biomarkers with the most reliable signals will be chosen for validation.

Researchers are exploiting extensive modelling to optimise the transduction properties of the metallic NANOANTENNA devices. As a result, they expect to arrive at the best geometry and size for maximum signal amplification. The team is currently experimenting with various bioreceptor candidates to determine the most effective NP functionalisation. Finally, several tests have been completed on the way to defining prototype characteristics. The team is spreading the word through the public area of the project website, a leaflet promoting the project, a Wikipedia page and several workshops. The first articles have already been published in peer-reviewed scientific journals.

NANOANTENNA optical biosensor technology is poised to revolutionise early diagnosis of diseases leading to rapid intervention and improved patient outcomes. Although it will be validated with two selected biomarkers, the concept paves the way for development of tailor-made sensors for any pathology for which biomarkers have been identified.

related link: http://cordis.europa.eu/result/brief/rcn/12406_en.html