Patent ID: 11946930
Assignee: HOFFMANN-LA ROCHE, INC.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A device for use in the detection of binding affinities, the device comprising
a substrate and a leakproof planar waveguide arranged thereon, the planar waveguide having a refractive index higher than the refractive index of the substrate, as well as a length and a width and an outer surface opposite to the substrate on which the planar waveguide is arranged,
a grating arranged on the planar waveguide, the grating comprising grating lines extending in the direction of the width of the planar waveguide with a grating period in the direction of the length of the planar waveguide which is less than 1 micrometer, for in operation coupling coherent light of a predetermined wavelength incident on the grating into the planar waveguide such that the coherent light coupled into the planar waveguide propagates through the planar waveguide in a predetermined propagation direction that corresponds to the direction of the length of the planar waveguide, with an evanescent field of the coherent light propagating along the outer surface of the planar waveguide,
a decoupler arranged on the outer surface of the planar waveguide spaced apart from the grating in the predetermined propagation direction by a distance of at least 10 micrometers,
wherein the decoupler on the outer surface of the planar waveguide comprises receptor molecules arranged on the outer surface of the planar waveguide, the receptor molecules being capable of binding target samples to the receptor molecules, wherein the receptor molecules are arranged along a plurality of straight parallel lines which are spaced from each other such that in operation a portion of the coherent light of the evanescent field diffracted by the target samples bound to the receptor molecules is decoupled from the planar waveguide as a collimated beam of diffracted coherent light propagating away from the planar waveguide in a predetermined detection direction,
wherein the decoupler on the outer surface of the planar waveguide further comprises filler molecules arranged on the outer surface of the planar waveguide in interstices formed between the straight parallel lines along which the receptor molecules are arranged, the filler molecules being incapable of binding the target samples to the filler molecules,
and wherein the receptor molecules arranged along the predetermined straight lines and the filler molecules arranged in the interstices between the predetermined straight lines together form an optically smooth area on the surface of the planar waveguide, the optically smooth area having the same refractive index and a uniform height relative to the outer surface of the planar waveguide that varies by no more than 1 nanometer.