Experimental study of sensitivity enhancement in surface plasmon resonance biosensors by use of periodic metallic nanowires.
We have experimentally confirmed sensitivity enhancement of a nanowire-based surface plasmon resonance (SPR) sensor structure. Gold nanowires with periods of 200 and 500 nm were fabricated, respectively, by electron-beam and interference lithography on a gold/SF10 substrate. Sensitivity enhancement was measured to be 44% compared with a conventional thin-film-based SPR structure for nanowires of 200 nm period and 31% for 500 nm when evaluated using ethanol at a varied concentration. This result is consistent with numerical data. Surface roughness is responsible for sensitivity reduction by more than 10%. More significant sensitivity improvement can be achieved by inducing strong localized plasmon coupling with finer nanowires.
Byun
Kyung Min
KM
School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-742, Korea.
Yoon
Soon Joon
SJ
Kim
Donghyun
D
Kim
Sung June
SJ
D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D000431:Ethanol / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000295:instrumentation / Q000379:methods*
D000431:Ethanol; D006046:Gold