Surface-plasmon optical-heterodyne clock biosensor

0499896 - ÚFE 2019 RIV CH eng J - Journal Article
Giorgini, A. - Avino, S. - Malara, P. - Zullo, R. - Natale, D.P. - Mrkvová, Kateřina - Homola, Jiří - Gagliardi, G.
Surface-plasmon optical-heterodyne clock biosensor.
Sensors and Actuators B - Chemical. Roč. 273, 10 November (2018), s. 336-341. E-ISSN 0925-4005
R&D Projects: GA ČR(CZ) GBP205/12/G118
Grant - others:AV ČR(CZ) AP1101
Program: Akademická prémie - Praemium Academiae
Institutional support: RVO:67985882
Keywords : Biosensing * Optical resonator * Surface plasmon resonance
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 6.393, year: 2018

Surface-plasmon resonance (SPR) sensors represent a formidable technology for molecular biology and bioanalytics applications. Here, we devise a new interrogation architecture that transforms a standard SPR chip into an optical-heterodyne clock detector comparable with the best SPR instruments. The key ingredients are (i) the conversion of refractive-index changes on the SPR chip into frequency shifts of an oscillatory electronic signal (ii) a differential probe & reference optical-cavity scheme that cancels out most source/detector noise contributions. A rigorous characterization of the sensor performance with the integration time demonstrates a refractive-index resolution on the 10(-8)-RIU level over a 1-s timescale using a bare, unstabilized SPR element. A bio-sensing test with a functionalized surface interfaced with a microfluidic flow-cell is carried out, showing detection of streptavidin via covalent bond down to concentrations of 90 fg/mm(2)
Permanent Link: http://hdl.handle.net/11104/0292084