Photonic antennas for ultra-sensitive biomolecular detection

Nanophotonics offer new opportunities to further improve single molecule optical detection beyond the diffraction limit. We exploit novel concepts of photonic antennas to generate new bionanophotonic tools for ultrasensitive detection of individual biomolecules in the micro-molar range. The major goal is to engineer photonic antenna devices to concentrate the light into nanometre-scale illumination volumes and simultaneously enhance the molecular emission. Single molecule spectroscopy techniques such as fluorescence correlation spectroscopy (FCS) and fluorescence resonance energy transfer (FRET) can greatly benefit from photonic nanoantennas to enter a new dimension of higher sensitivities at molecular concentrations reaching physiological conditions.

Current efforts in our Lab focus on the design and fabrication of hybrid nano-antennas arrays based on different metals to achieve maximum single molecule sensitivity. For this, we combine gold as the best material for field enhancement with aluminium as surrounded antenna material to provide maximum background suppression. We are also pushing the versatility of antenna arrays towards high-throughput single biomolecule detection by enabling multi-colour detection at the nanoscale (i.e., broadband operation in the visible regime) and increasing the throughput of single molecule analysis by fabricating highly packed antennas together with wide field-illumination and detection. Our current record is the detection of individual molecules in three different colours from 1000 different antennas in a quasi-simultaneous manner.