Processes, compositions, and sensors for sensing a variety of toxic chemicals based on colorimetric changes. Exemplary process for sensing a toxic chemical includes contacting a toxic chemical, or byproduct thereof, with a sorbent that includes a porous metal hydroxide or a porous mixed-metal oxide/hydroxide and a transition metal reactant suitable to react with a toxic chemical or byproduct thereof. The sorbent is contacted with the toxic chemical or byproduct thereof for a sampling time. A difference between a post-exposure colorimetric state of the sorbent and a pre-exposure colorimetric state of the sorbent is determined to thereby detect exposure to, or the presence of, the toxic chemical or byproduct thereof.

Processes, compositions, and sensors for sensing a variety of toxic chemicals based on colorimetric changes. Exemplary process for sensing a toxic chemical includes contacting a toxic chemical, or byproduct thereof, with a sorbent that includes a porous metal hydroxide or a porous mixed-metal oxide/hydroxide and a transition metal reactant suitable to react with a toxic chemical or byproduct thereof. The sorbent is contacted with the toxic chemical or byproduct thereof for a sampling time. A difference between a post-exposure colorimetric state of the sorbent and a pre-exposure colorimetric state of the sorbent is determined to thereby detect exposure to, or the presence of, the toxic chemical or byproduct thereof.

A continuous glucose monitoring system may include a hand-held monitor, a transmitter, an insulin pump, and an orthogonally redundant glucose sensor, which may comprise an optical glucose sensor and a non-optical glucose sensor. The former may be a fiber optical sensor, including a competitive glucose binding affinity assay with a glucose analog and a fluorophore-labeled glucose receptor, which is interrogated by an optical interrogating system, e.g., a stacked planar integrated optical system. The non-optical sensor may be an electrochemical sensor having a plurality of electrodes distributed along the length thereof. Proximal portions of the optical and electrochemical sensors may be housed inside the transmitter and operationally coupled with instrumentation for, e.g., receiving signals from the sensors, converting to respective glucose values, and communicating the glucose values. The sensors' distal portions may be inserted into a user's body via a single delivery needle and may be co-located inside the user's body.

The invention relates to a polymer matrix for optical sensing of pH and/or carbon dioxide, and a process for producing the polymer matrix. Also discussed is an optical sensor for optical sensing of pH and/or carbon dioxide comprising the polymer matrix of the invention, and a method for making the optical sensor. The invention further provides a method of measuring the pH and/or the carbon dioxide content of a sample, using the sensor of the invention. The optical sensor is useful in measuring the pH and/or the carbon dioxide content of biological samples such as blood.

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).

Method and compositions using transition metal salts and/or ammonium chloride to liberate toxins and other molecules from cyanobacteria, useful for assaying for total cyanobacterial toxins in lakes, reservoirs and other waters.

An optochemical sensor unit including: an optical waveguide; a transmitting unit for emitting a first transmission signal for exciting a luminophore; a receiving unit for receiving a received signal comprising a signal component emitted by the excited luminophore; a measuring chamber for receiving a fluid, wherein the fluid includes magnetic microspheres; a membrane arranged between the measuring chamber and a measuring medium for exchanging an analyte between the measuring medium and the fluid in the measuring chamber, wherein the measuring diaphragm is impermeable to the magnetic microspheres; and an electromagnet for attracting magnetic microspheres to a sensor membrane with a fluid-contacting surface and/or to a fluid-contacting surface of the optical waveguide, or to a surface of a transparent substrate layer of the optical sensor unit that is connected to the optical waveguide.

Described are sensors and methods of detecting hydrogen gas. The sensor includes a polymer matrix and a dye molecule in an amount sufficient such that exposure of the polymer matrix to hydrogen gas causes a change in a spectroscopic property of the dye molecule wherein the spectroscopic property includes at least one of color, absorbance, or luminescence. The polymer matrix may further include a catalyst, such as a transition metal, sulfonated Wilkinson's catalyst, colloidal Pt, sulfonated iridium cyclooctadiene triphenylphosphine, sulfonated rhodium cyclooctadiene triphenylphosphine, sulfonated ruthenium triphenylphosphine, or combinations thereof. Embodiments of the sensor may further include a gas permeable, water impermeable membrane, an outer covering, or combinations thereof.

An optochemical sensor for determining a pH of a measured medium includes a sensor membrane having an analyte-sensitive layer. The sensor membrane has a first luminophoric dye in the form of an indicator dye and a second luminophoric dye in the form or a reference dye. At least one of the two aforementioned dyes is contained in the analyte-sensitive layer, and one of the two aforementioned dyes has an inorganic framework structure. At least one inorganic or organic receptor group, which is protolyzable, is bonded to the framework structure.

An sensor (2) based on an optical-sensing technique measures gaseous or dissolved analytes in a measurement medium (4). The sensor has a sensor housing (6) and an optochemical sensor element (20, 220) arranged within the sensor housing. The optochemical sensor element (220) has a substrate (222), a sensing layer (224) and a barrier layer (230). The barrier layer is arranged to protect the optochemical sensor element from interfering substances (234) present in the measurement medium.