title: Toward single-molecule detection with sensors based on propagating surface plasmons.
abstract: Surface plasmon resonance (SPR) sensors are known to be able to detect very low surface concentrations of (bio)molecules on macroscopic areas. To explore the potential of SPR biosensors to achieve single-molecule detection, we have minimized the read-out area (to ~64 μm2) by employing a sensor system based on spectroscopy of surface plasmons generated on a diffractive structure via a microscope objective and light collection through a small aperture. This approach allows for decreasing the number of detected molecules by 3 orders of magnitude compared to state-of-the-art SPR sensors. A protein monolayer has been shown to produce a response of 5000 times the baseline noise, suggesting that as few as ~500 proteins could be detected by the sensor.
authors.affiliation: Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Kvasnička
authors.forename: Karel
authors.initials: K
authors.lastname: Chadt
authors.forename: Milan
authors.initials: M
authors.lastname: Vala
authors.forename: Markéta
authors.initials: M
authors.lastname: Bocková
authors.forename: Jiří
authors.initials: J
authors.lastname: Homola
mesh_terms: D055620:Optical Phenomena; D019809:Streptavidin / Q000378:metabolism; D020349:Surface Plasmon Resonance / Q000295:instrumentation / Q000379:methods*; D013997:Time Factors
chemical_list: D019809:Streptavidin