title: 2D label-free imaging of resonant grating biochips in ultraviolet.
abstract: 2D images of label-free biochips exploiting resonant waveguide grating (RWG) are presented. They indicate sensitivities on the order of 1 pg/mm2 for proteins in air, and hence 10 pg/mm2 in water can be safely expected. A 320x256 pixels Aluminum-Gallium-Nitride-based sensor array is used, with an intrinsic narrow spectral window centered at 280 nm. The additional role of characteristic biological layer absorption at this wavelength is calculated, and regimes revealing its impact are discussed. Experimentally, the resonance of a chip coated with protein is revealed and the sensitivity evaluated through angular spectroscopy and imaging. In addition to a sensitivity similar to surface plasmon resonance (SPR), the RWGs resonance can be flexibly tailored to gain spatial, biochemical, or spectral sensitivity.
authors.affiliation: Thales Research & Technology, 1 avenue Fresnel, Campus Polytechnique, 91767 Palaiseau, France. kristelle_robin@yahoo.fr
authors.forename: K
authors.initials: K
authors.lastname: Bougot-Robin
authors.forename: J-L
authors.initials: JL
authors.lastname: Reverchon
authors.forename: M
authors.initials: M
authors.lastname: Fromant
authors.forename: L
authors.initials: L
authors.lastname: Mugherli
authors.forename: P
authors.initials: P
authors.lastname: Plateau
authors.forename: H
authors.initials: H
authors.lastname: Benisty
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D040081:Protein Array Analysis / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D013194:Staining and Labeling; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014159:Transducers; D014466:Ultraviolet Rays