Abstract: An array of molecular chains is added to a dielectric material between two electrodes of a capacitive affinity sensor. Such an array of molecular chains greatly changes dielectric properties between the two electrodes to greatly enhance sensitivity of the sensor. In a sensor using direct binding, a viral fragment is bound to the sensor's surface. A molecular chain, comprising an anti-viral antibody, an anti-human antibody, and a protein molecule, binds to the viral fragment. In a sensor using competitive binding a hapten is bound to the sensor's surface. A molecular chain, comprising an antibody with attached aliphatic hydrocarbons, binds to the hapten. A free analyte competes with the hapten to bind with the antibody.

Abstract: A dielectric material of a capacitive affinity sensor has a three-dimensional molecular binding site array. A glass base is layered with a binding agent like silane from which a polymeric backbone like polylysine extends. The polymeric backbone is prepared to accept receptor molecules like cortisol hemisuccinate to bind a specific antibody. Such an array changes dielectric properties between the two electrodes of the capacitive affinity sensor to greatly enhance sensitivity of the sensor.

Abstract: The invention relates to a continuous flow competitive assay system for the detection and measurement of chemical and biochemical analytes. It is a time-based, continuous on-line measurement of analyte concentrations comprising three functional assemblies connected in series: a sampler, a reactor and a detector. Tagged immunochemical discharged from the reactor is detected in the detector which contains a model of system response with the tagged immunochemical and keeps track of the amount of tagged immunochemical lost during the course of the operation of the reactor.

Abstract: A capacitive chemical sensor is disclosed that uses an ion exchange layer to detect analyte ions in a liquid medium. An exchange mechanism occurs on the surface of the ion exchange layer, wherein a portion of the counter-ions are removed from the surface in favor of analyte ions. The resulting movement of counter-ions from the surface of the ion exchange layer alters the dielectric constant of the liquid medium along the surface of the ion exchange layer. This change in dielectric constant produces a change in capacitance of the capacitive chemical sensor.

Abstract: A differential polarimeter is disclosed for detecting changes in optical rotation between a test cell and reference cell. The test cell contains a fluid sample exposed to an analyte specific enzyme; the reference cell contains a fluid sample not exposed to the enzyme. To enhance the sensitivity of the system a phase sensitive differential polarimetric technique is taught. In this technique, the phase difference between two resulting sinewave voltages is a measure of analyte concentration.

Abstract: An apparatus for detecting the concentration of certain analytes, including hydrocarbons, in a liquid medium, is disclosed. The apparatus uses a planar or "open" capacitor containing an active layer. In response to selected analyte in the liquid medium, the active layer causes capacitance to decrease with increasing analyte concentration. The capacitance decreases because higher dielectric water molecules are displaced from a region of the capacitor's electric field. For certain hydrocarbon analytes having high Henry's Law constants, the active layer causes bubbles to nucleate in the liquid medium on the surface of the active layer. Bubble formation displaces water molecules and decreases capacitance.

Abstract: This invention relates to an apparatus and method for regulating the exposure of active surfaces by covering the surface with an erodible protection coating. The rate of erosion is controlled by chemical and/or physical means so that the surface is progressively and gradually exposed.

Abstract: A method and apparatus is disclosed for optically monitoring the concentration of singlet oxygen produced during photoradiation. A composite optical emission in the 1.27 micron frequency band is detected and electrically processed to separate a first component due to the decay of singlet oxygen from a second unwanted component due to the fluorescence of the photosensitizing dye.A pulsed excitation source is used to excite the photosensitizing dye and a time domain signal processor, such as a box-car integrator, is used to separate and process the singlet oxygen emission component in the time domain.The magnitude and/or other characteristics of the singlet oxygen emission component can be used to determine properties of complex biological or other media. In a therapeutic environment the magnitude and/or other characteristics of the singlet oxygen emission can be used by the treating physician to set a therapeutic light dosimetry.

Abstract: A method and apparatus is disclosed for optically monitoring the concentration of singlet oxygen produced during photoradiation. A composite optical emission in the 1.27 micron frequency band is detected and electrically processed to separate a first component due to the decay of singlet oxygen from a second unwanted component due to the fluorescence of the photosensitizing dye.A chopped CW excitation source is used to excite the photosensitizing dye and a signal processing means such as a lock-in amplifier is used to separate the singlet oxygen emission component which appears out of phase from the chopped excitation signal and the in-phase photosensitizer fluorescence.The magnitude and/or other characteristics of the singlet oxygen emission component can be used to determine properties of complex biological or other media. In a therapeutic environment the magnitude and/or other characteristics of the singlet oxygen emission can be used by the treating physician to set a therapeutic light dosimetry.