Novel chemical sensors that improve detection and quantification of CO.sub.2 are critical to ensuring safe and cost-effective monitoring of carbon storage sites. Fiber optic (FO) based chemical sensor systems are promising field-deployable systems for real-time monitoring of CO.sub.2 in geological formations for long-range distributed sensing. In this work, a mixed-matrix composite integrated FO sensor system was developed that reliably operates as a detector for gas-phase and dissolved CO.sub.2. A mixed-matrix composite sensor coating on the FO sensor comprising plasmonic nanocrystals and zeolite embedded in a polymer matrix. The mixed-matrix composite FO sensor showed excellent reversibility/stability in a high humidity environment and sensitivity to gas-phase CO.sub.2 over a large concentration range. The sensor exhibited the ability to sense CO.sub.2 in the presence of other geologically relevant gases, which is of importance for applications in geological formations. A prototype FO sensor configuration which possesses a robust sensing capability for monitoring dissolved CO.sub.2 in natural water was demonstrated. Reproducibility was confirmed over many cycles, both in a laboratory setting and in the field.

Disclosed herein are embodiments of sensor devices comprising a sensing component able to determine the presence of, detect, and/or quantify detectable species in a variety of environments and applications. The sensing components disclosed herein can comprise MOF materials, plasmonic nanomaterials, redox-active molecules, a metal, or any combinations thereof. In some exemplary embodiments, optical properties of the plasmonic nanomaterials and/or the redox-active molecules combined with MOF materials can be monitored directly to detect analyte species through their impact on external conditions surrounding the material or as a result of charge transfer to and from the plasmonic nanomaterial and/or the redox-active molecule as a result of interactions with the MOF material.

An apparatus adapted to perform spectrometric measurements, said apparatus comprising a tunable laser light source adapted to generate a laser light with an excitation wavelength supplied to an optical sensor which produces a sample specific response light signal; an optical reference filter adapted to measure laser light with the excitation wavelength fed back as a reference signal to provide wavelength calibration of the tunable laser light source; at least one optical measurement filter adapted to measure the sample specific response light signal produced by the optical sensor, wherein the optical reference filter and the at least one optical measurement filter are thermally coupled to maintain a constant wavelength relationship between the filter characteristics of the optical filters.

Distributed fiber optic sensors formed by covering the fibers with tubing are provided. The tubing including responsive materials formulated or configured to, responsive to exposure to one of a target chemical species and a target radiation particle, change a relative size and generate a localized effect on or in the optical fiber.

A sensing system for characterizing analytes of interest in a sample comprises a photonic integrated circuit with an integrated interferometer. The integrated interferometer is configured for spectroscopic operation. The integrated interferometer comprises at least a sensing arm and a reference arm, both the sensing arm and the reference arm having an exposable segment available for interaction with the sample, whereby the exposable segment of the reference arm has an optical path length which is smaller than twice the optical path length of the exposable segment of the sensing arm. The exposable section of the sensing arm is selective to the analyte of interest, whereas the exposable section of the reference arm is not selective to the analyte of interest.

A method of directly measuring moisture content in an oil-filled transformer includes using an optical fiber that having a grating sensor, such as a Fiber Bragg grating, defined in the optical fiber. The various conductors (windings) in the transformer are insulated using an insulator such as paper and insulating oil is filled inside the transformer. Moisture in the transformer is absorbed by the paper that surrounds the windings. A moisture content at a specific location can be measured by placing the optical fiber with the grating sensor directly at the specific location to be measured. A physical parameter of the paper that absorbed moisture changes over time, causing a change in the grating sensor of the optical fiber which changes the spectral response of optical signals that are reflected by the grating sensor. The method provides an accurate method of measuring the moisture inside the transformer at the specific location.

A planar waveguide device (PWD) for interacting with a fluid (FLD) is disclosed, the planar waveguide device (PWD) comprising a waveguide layer (WGL) for supporting optical confinement, a coupling arrangement (CPA) for in-coupling and out-coupling of light into and from the waveguide layer (WGL), a fluid zone (FZN) for accommodating the fluid (FLD), a filter layer (FTL) arranged between the fluid zone (FZN) and the waveguide layer (WGL) in an interaction region (IAR) of the waveguide layer (WGL),
wherein the filter layer (FTL) comprises filter openings (FOP) arranged to allow the fluid (FLD) to interact with an evanescent field of light guided by the waveguide layer (WGL),
wherein the filter openings (FOP) are adapted to prevent particles (PAR) larger than a predefined size from interacting with said evanescent field,
wherein the filter openings (FOP) are arranged as line openings having their longitudinal direction in parallel with the direction of propagation (DOP) of light guided by the waveguide layer (WGL).

The invention relates to an electronic device for analyzing an analyte (2) present in a fluid, comprising: a consumable and interchangeable sensor (10) comprising temporary receptors (14) capable of an interaction with the analyte present in the fluid, causing a change in local property; a sensor holder (50) in which the sensor is intended to be reversibly placed; and a transducer for the change in local property (130, 131; 230, 231), positioned on the sensor and/or on the sensor holder and able to convert the change in local property into an electronic signal expressing the change in local property. The sensor comprises a protection (17) for the temporary receptors. The invention also relates to the method of manufacturing this device, as well as to the consumable and interchangeable sensor and to its method of manufacturing.

The present disclosure presents nanostructure-based localized surface plasmon resonance systems and related methods. In this regard, a method comprises applying a body fluid sample to a metal surface of the nanostructure-based LSPR biosensor with linker, intermediate, and capture/probe antibodies; illuminating the metal surface of the nanostructure-based LSPR biosensor with the monochromatic, broadband, or laser light; measuring an intensity or spectrum of absorbed, reflected, transmitted, or scattered exiting light from the nanostructure-based LSPR biosensor having the body fluid sample and comparing the measured intensity or spectrum with a reference intensity; detecting a spectral shift of exiting light from the nanostructure-based LSPR biosensor having the body fluid sample; and signaling that the body fluid sample is positive for a presence of a particular biomaterial in response to detecting the spectral shift of the exiting light, wherein the biomaterial has binded or adsorbed to the metal surface of the nanostructure-based LSPR biosensor.

Distributed fiber optic chemical and radiation sensors formed by coating the fibers with certain types of response materials are provided. For distributed chemical sensors, the coatings are reactive with the targets; the heat absorbed or released during a reaction will cause a local temperature change on the fiber. For distributed radiation sensors, coating a fiber with a scintillator enhances sensitivity toward thermal neutrons, for example, by injecting light into the fiber. The luminescent components in these materials are taken from conjugated polymeric and oligomeric dyes, metal organic frameworks with sorbed dyes, and two-photon-absorbing semiconductors. The compositions may exhibit strong gamma rejection. Other scintillators combining luminescent materials with neutron converters are available. With a multiple-layer coating, it may be possible to identify the presence of both neutrons and gamma rays, for example. Coatings may be applied during manufacture or in the field.