Abstract: Simplicity, sensitivity and versatility of optical sensors based on competitive immunoassays using antibody-antigen reactions are achieved by solid-state, single-step reactions which permit accurate sensitive qualitative and quantitative information to be obtained without human participation. All of the chemistry-biochemistry is an inherent part of the sensor. A direct reaction occurs when the sample (antigen) is brought in contact with the sensor. The sensitivity of the competitive immunoassay optical sensor is controlled and increased by selecting a tag for the antigen or altering the attachment of a tag to an antigen so that the binding of tagged antigen to an antibody is decreased relative to the binding of untagged antigen to the antibody. The user can vary size, molecular weight and geometric configuration of the tagged antigen.

Abstract: Simplicity, sensitivity and versatility of optical sensors based on competitive immunoassays using antibody-antigen reactions are achieved by solid-state, single-step reactions which permit accurate sensitive qualitative and quantitative information to be obtained without human participation. All of the chemistry-biochemistry is an inherent part of the sensor. A direct reaction occurs when the sample (antigen) is brought in contact with the sensor. The sensitivity of the competitive immunoassay optical sensor is controlled and increased by selecting a tag for the antigen or altering the attachment of a tag to an antigen so that the binding of tagged antigen to an antibody is decreased relative to the binding of untagged antigen to the antibody. The user can vary size, molecular weight and geometric configuration of the tagged antigen.

Abstract: Waveguide sensors are formed on a chip package which contains at least one source and at least one detector. Simple waveguide elements are mounted on the chip. Waveguide defining elements can also be formed integrally with the chip package so that simple waveguide bodies can be inserted or removed. Various geometries of source, reference detector, and sensing detector can be produced. A liquid waveguide sensor is formed by filling a waveguide channel with a liquid reagent or reagents homogeneously dispersed in sol-gels. Sensing waveguides are made of or contain chemistries or biochemistries or are uncoated. Reference waveguides are made of or contain chemistries, biochemistries or materials which are inert to the analyte (sample) of interest. The chip geometries are such that absorption, fluorescence, and refractive index measurements can be made.

Abstract: Waveguide sensors are formed on a chip package which contains at least one source and at least one detector. Simple waveguide elements are mounted on the chip. Waveguide defining elements can also be formed integrally with the chip package so that simple waveguide bodies can be inserted or removed. Various geometries of source, reference detector, and sensing detector can be produced. A liquid waveguide sensor is formed by filling a waveguide channel with a liquid reagent.

Abstract: A solid state optical sensor for CO has a sensing material which includes a molybdenum, tungsten or vanadium color forming agent; a palladium, ruthenium or osmium catalyst; and an iron, chromium or cesium reversing agent. A redox property modifier and/or an interference suppressing agent may also be included. The chemistry is contained in a polymer embedding matrix, with permeation enhancer, if required. Solubility of the chemistry in the polymer matrix is enhanced by lipophilic counterions. The matrix with embedded sensing chemistry is coated on an optical substrate to form an optical transducer.

Abstract: In a sensor assembly, an optical fiber with a sensing region is connected at one end through a fiber guide tube to a detector housing containing a sensing detector. At the other end the fiber is connected through a fiber guide tube to a light source which has a reference detector mounted laterally thereto. The sensing and reference detectors are a matched pair of the same type. The guide tube in the source has a bevelled end which reflects a portion of light from the source to the reference detector.

Abstract: A molybdenum, tungsten or vanadium salt-palladium, ruthenium or osmium salt solution for CO detection is made reversible by addition of ferric, chromium (VI) or cerium (IV) ion. The system is made more CO specific by adding an interference control salt which forms white or colorless precipitates with interfering species. The operational and shelf life are extended by a mixture of counterions; the acetate counterion is particularly useful.

Abstract: A molybdenum salt-palladium salt solution for CO detection is made reversible by addition of ferric ion. The system is made more CO specific by adding an interference control salt which forms white or colorless precipitates with interfering species. The operational and shelf life are extended by a mixture of counterions; the acetate counterion is particularly useful.

Abstract: In a refractive index type optical sensor having a thin film metal clad on a waveguide to control leakage of light as a function of refractive index, light leakage occurs in the region where a discontinuity in refractive index occurs. A discontinuous clad with short, closely spaced segments maximizes light leakage and sensitivity over the length of the sensing region. Multiple sensing regions can be formed on a single waveguide.