Label-free high-throughput optical technique for detecting biomolecular interactions
View Patent ↗Methods and compositions are provided for detecting biomolecular interactions. The use of labels is not required and the methods can be performed in a high-throughput manner. The invention also provides optical devices useful as narrow band filters.
1. A biosensor comprising:
(a) a two-dimensional grating comprised of a material having a high refractive index, wherein the two-dimensional grating is comprised of a repeating pattern of lines;
(b) a substrate layer that supports the two-dimensional grating; and
(c) one or more specific binding substances immobilized on the surface of the two-dimensional grating opposite of the substrate layer;
wherein, when the biosensor is illuminated a resonant grating effect is produced on the reflected radiation spectrum, and wherein the depth and period of the two-dimensional grating are less than the wavelength of the resonant grating effect.
2. A detection system comprising the biosensor of claim 1 , a light source that directs light to the biosensor, and a detector that detects light reflected from the biosensor.
3. The detection system of claim 2 , further comprising a fiber probe comprising one or more illuminating optical fibers that are connected at a first end to the light source, and one or more collecting optical fibers connected at a first end to the detector, wherein the second ends of the illuminating and collecting fibers are arranged in line with a collimating lens that focuses light onto the biosensor.
4. The detection system of claim 3 , wherein the illuminating fiber and the collecting fiber are the same fiber.
5. The detection system of claim 2 , wherein the light source illuminates the biosensor from its top surface or from its bottom surface.