title: Label-free slot-waveguide biosensor for the detection of DNA hybridization.
abstract: A finite element method based on the full-vectorial H-field formulation has been employed to achieve the maximum field penetration in the sensing medium of the slot-waveguide-based ring resonator biosensor. The use of nanometer scale guiding structure where optical mode is confined in a low-index region permits a very compact sensor with high optical intensity in the region, which makes it possible to detect minimum refractive index change, and offers higher sensitivities. We analyze the change in effective refractive index of mode, sensitivity, and power confinement of the proposed slot-waveguide-based ring resonator biosensor for the detection of DNA hybridization. The biosensor exhibited theoretical sensitivity of 856 nm per refractive index unit (RIU) and a detection limit of 1.43×10(-6)  RIU.
authors.affiliation: School of Engineering and Mathematical Sciences, City University, Northampton Square, London EC1V 0HB, UK. tuffaildar@gmail.com
authors.forename: Tuffail
authors.initials: T
authors.lastname: Dar
authors.forename: Jiri
authors.initials: J
authors.lastname: Homola
authors.forename: B M Azizur
authors.initials: BM
authors.lastname: Rahman
authors.forename: Muttukrishnan
authors.initials: M
authors.lastname: Rajarajan
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000295:instrumentation*; D017076:Computer-Aided Design; D004247:DNA / Q000032:analysis / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017403:In Situ Hybridization / Q000295:instrumentation*; D008969:Molecular Sequence Data; D036103:Nanotechnology / Q000295:instrumentation*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D013194:Staining and Labeling
chemical_list: D004247:DNA