Authors
Julien Proust, Jérôme Martin, Davy Gérard, Jean-Louis Bijeon, Jerome Plain,
Title
Detecting a zeptogram of pyridine with a hybrid plasmonic-photonic nanosensor
In
ACS Sensors
Volume
4
Pages
586–594
Publisher
American Chemical Society
Year
2019
Publisher's URL
https://pubs.acs.org/doi/abs/10.1021/acssensors.8b01068
Indexed by
Abstract
Thanks to their small sensing volume, nanosensors based on localized surface plasmon resonances (LSPR) allow the detection of minute amounts of analytes, down to the single molecule limit. However, the detected analytes are often large molecules, such as proteins. The detection of small molecules remains largely unexplored. Here, we use a hybrid photonic-plasmonic nanosensor to detect a small target molecule (pyridine). The sensor's design is based on a dielectric photonic microstructure acting as an antenna, which efficiently funnels light towards a plasmonic transducer and enhance the detection efficiency. This sensor exhibits a limit of detection as small as 10-14 mol.L-1 . Using a calibration procedure based on electrodynamical numerical simulations, we compute the number of detected molecules. This yields a limit of detection in mass of 4 zeptograms (1 zg = 10-21 g), a record value for plasmonic molecular sensors. Our system can hence be seen as an optical molecular weighing scale, enabling room temperature detection of mass at the zeptogram scale.
Affiliations
Offprint