An optical fiber includes a graphene oxide and a reduced graphene oxide and a gas sensor includes the optical fiber. A method for manufacturing the optical fiber includes coating a graphene oxide layer and reducing a part of the graphene oxide layer, and a method for manufacturing the gas sensor includes coating a graphene oxide layer and reducing a part of the graphene oxide layer.

The invention is a SPR sensor that comprises a multi-layered plasmonic structure on a substrate for sensing. The SPR sensor has an enhanced figure of merit and lower limit of detection (system noise divided by the sensitivity) by at least two orders of magnitude than prior art SPR sensors. The plasmonic structure of the invention comprises a Nanostructured Porous Metal Layer (NPML) and at least one of: (a) buried dielectric layer under the nano-porous metal layer; (b) a nano-dimensional high index layer on top of the metal layer; and (c) a molecular layer for bio-functionalization adjacent to an analyte layer. The invention also encompasses many embodiments of measuring systems that comprise the SPR sensors of the invention with improved signal to noise ratio.

The present disclosure is to provide a measurement chip, a measuring device, and a measuring method which can accurately estimate an analyte concentration with a simple configuration. A measurement chip may include a propagation layer, an introductory part, a drawn-out part and a reaction part. Through the propagation layer, light may propagate. The introductory part may introduce the light into the propagation layer. The drawn-out part may draw the light from the propagation layer. The reaction part may have, in a surface of the propagation layer where a reactant that reacts to a substance to be detected is formed, an area where a content of the reactant changes monotonously in a perpendicular direction perpendicular to a propagating direction of the light, over a given length in the propagating direction.

A label-free optical biosensing system and method provide high sensitivity and specificity for in situ detection and activity estimation of serotypes, such as Botulinum Neurotoxins (BoNT). Pre-fabricated thin-film support structures are treated with a competitive immunoassay coupled to a biochemical cascade reaction, which provides optical signal amplification. When the thin-film support structures receive a target analyte and are exposed to polychromatic light, reaction products cause a change in average refractive index which appears in reflectivity spectra measured by an optical interferometer. Optical signal amplification enables a linear response for serotype concentrations of only a few picograms per millilitre, as well as a level-of-detection threshold of 5.0 picograms per millilitre or less. The specificity and selectivity of the method have been verified in studies using various combinations of different serotypes as a target analyte. Similarly, the serotype activity is estimated by an adjunct sensing platform.

According to various embodiments, there is provided a sensor arrangement including a filter configured to provide an output signal having an output wavelength, the output wavelength having a dependence on a temperature of the filter; a temperature module configured to change the temperature of the filter; a controller circuit configured to control the temperature module for changing the temperature of the filter until the output wavelength increases with decreasing temperature; and a determination circuit configured to determine a dew point of an environment surrounding the sensor arrangement, based on a minimum value of the output wavelength and the dependence.

The present disclosure provides a diffraction based biosensor containing at least two diffraction gratings. The first grating is referred to as an in-coupling diffraction grating and the coherent light source (laser) is directed to illuminate the in-coupling grating, and the biosensor is configured such that a selected order of the light beam diffracted from the in-coupling diffraction grating illuminates a second biosensor grating coated with analyte-specific receptors which are selected to preferentially bind with analytes being tested for that may or may not be located in a sample being tested.

Disclosed are a biochip capable of detecting and analyzing multivalent bindings between target protein and binding mediator from monovalent bindings and a method for manufacturing the same. A biochip according to an embodiment comprises: a hydrogel functional layer on which a binding mediator is formed and of which physical properties are changed by a reaction between target protein to be introduced and the binding mediator; and a transducer configured to deliver a displacement signal corresponding to a change in the physical properties of the hydrogel functional layer to an analysis instrument, wherein the reaction is multivalent bindings between the target protein and the binding mediator, and de-swelling occurs in at least a portion of the hydrogel functional layer by the multivalent bindings.

The present invention relates to a reusable optical fiber aptasensor using a photo-thermal effect, and more particularly, to a reusable optical fiber aptasensor using white light and a laser. The aptasensor includes a light emitting unit for selectively emitting one of white light and a laser, a sensor unit including a plurality of aptamers, a plurality of gold nanorods, and a silver mirror, a detector for analyzing a wavelength of inputted light, and an optical fiber for connecting the light emitting unit with the sensor unit, and connecting the detector with the sensor unit, wherein the light emitted from the light emitting unit is totally reflected in the optical fiber and irradiated to the sensor unit, and light reflected from the silver mirror of the sensor unit is irradiated to the detector. Accordingly, the aptasensor easily measures concentration of a target material in a sample using the optical fiber.

A guided mode resonance device, comprisinga substrate,a waveguide,a grating structure associated with said waveguide, said grating structure being arranged to an incident surface of said substrate, said incident surface being intended to receive an incident light beam provided by at least one light source, said incident light beam having an incident angle, defined relative to the normal of said waveguide, said grating structure comprising at least one elementary structure comprising at least a first-type grating structure and at least a second-type grating structure,wherein:said waveguide is arranged to transfer light from the first-type grating structures to the second-type grating structure and also to transfer light from the second-type grating structures to the first-type grating structure,said first-type grating structure is arranged to couple out a first light beam,said second-type grating structure is arranged to couple out a second light beam,said first light beam having a different spectral distribution than said second light beam.

An optical sensor sheet includes a plurality of optical sensor chips to change a characteristic of an input optical signal depending on a state of a specimen and to output an optical signal with a changed characteristic, an optical path to propagate an optical signal input to and output from the plurality of optical sensor chips, and a sheet member including the plurality of optical sensor chips.