title: Polarization-extinction-based detection of DNA hybridization in situ using a nanoparticle wire-grid polarizer.
abstract: Metallic wires can discriminate light polarization due to strong absorption of electric fields oscillating in parallel to wires. Here, we explore polarization-based biosensing of DNA hybridization in situ by employing metal target-conjugated nanoparticles to form a wire-grid polarizer (WGP) as complementary DNA strands hybridize. Experimental results using gold nanoparticles of 15 nm diameter to form a WGP of 400 nm period suggest that polarization extinction can detect DNA hybridization with a limit of detection in the range of 1 nM concentration. The sensitivity may be improved by more than an order of magnitude if larger nanoparticles are employed to define WGPs at a period between 400 and 500 nm.
authors.affiliation: School of Electrical and Electronic Engineering, Yonsei University, Seoul, South Korea.
authors.forename: Hojeong
authors.initials: H
authors.lastname: Yu
authors.forename: Youngjin
authors.initials: Y
authors.lastname: Oh
authors.forename: Soowon
authors.initials: S
authors.lastname: Kim
authors.forename: Seok Ho
authors.initials: SH
authors.lastname: Song
authors.forename: Donghyun
authors.initials: D
authors.lastname: Kim
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017403:In Situ Hybridization / Q000295:instrumentation*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*