Abstract: The invention relates to an electrochemical sensor and method for providing the sensor having an insulator, an electrode deposited on the insulator, an electrolytic material in contact with the electrode for providing an electrical connection, and a cooling and heating element in contact with the insulator and spaced apart from the electrode for adjusting a temperature of the sensor.

Abstract: Disclosed herein is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system. The method for sampling disclosed herein comprises the steps of pre-wetting the sampling swab to a level below that of absorptive saturation; wiping a surface to be sampled with the swab with sufficient pressure to expel the wetting solution onto the surface; and, after reducing the pressure exerted on the sampling swab, further wiping the surface to re-absorb the moisture from the surface.

Abstract: Disclosed herein is a polymeric sampling swab for obtaining samples of an analyte of interest from solid surfaces or from liquid substances. The polymeric material of which the swab is composed is characterized by a high resistance to chemical and mechanical degradation. The sampling swab of the present invention is further characterized by a high internal void volume and a high absorptive capacity for fluids. The swab of the present invention is particularly suited for obtaining samples for use in chemiluminescent assays for, among other analytes of interest, microbial contamination. Also disclosed is a polymeric disc for loading with reagent mixtures suitable for use in bioluminescent assay procedures. The reagent disc of the invention is characterized by high resistance to chemical and mechanical degradation. In addition, the disc has a high void volume and high absorptive capacity.

Abstract: A hand-held assay device measuring chemiluminescence generated by as ample of ATP or other entity capable of chemically reacting to generate photoluminescence includes a photodiode detecting light which is emitted from the sample to produce a sample signal, another photodiode generating a reference signal in response to environmental changes, switched integrators amplifying the sensor signal over a controllable integration time to detect an output signal indicative of the presence of the sample.

Abstract: Disclosed is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system.

Abstract: Disclosed is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system.

Abstract: Disclosed herein is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system. The method for sampling disclosed herein comprises the steps of pre-wetting the sampling swab to a level below that of absorptive saturation; wiping a surface to be sampled with the swab with sufficient pressure to expel the wetting solution onto the surface; and, after reducing the pressure exerted on the sampling swab, further wiping the surface-to re-absorb the moisture from the surface.

Abstract: Disclosed herein is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system. The method for sampling disclosed herein comprises the steps of pre-wetting the sampling swab to a level below that of absorptive saturation; wiping a surface to be sampled with the swab with sufficient pressure to expel the wetting solution onto the surface; and, after reducing the pressure exerted on the sampling swab, further wiping the surface-to re-absorb the moisture from the surface.

Abstract: Disclosed herein is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system. The method for sampling disclosed herein comprises the steps of pre-wetting the sampling swab to a level below that of absorptive saturation; wiping a surface to be sampled with the swab with sufficient pressure to expel the wetting solution onto the surface; and, after reducing the pressure exerted on the sampling swab, further wiping the surface to re-absorb the moisture from the surface.

Abstract: Disclosed herein is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system. The method for sampling disclosed herein comprises the steps of pre-wetting the sampling swab to a level below that of absorptive saturation; wiping a surface to be sampled with the swab with sufficient pressure to expel the wetting solution onto the surface; and, after reducing the pressure exerted on the sampling swab, further wiping the surface to re-absorb the moisture from the surface.

Abstract: Disclosed herein is a polymeric sampling swab for obtaining samples of an analyte of interest from solid surfaces or from liquid substances. The polymeric material of which the swab is composed is characterized by a high resistance to chemical and mechanical degradation. The sampling swab of the present invention is further characterized by a high internal void volume and a high absorptive capacity for fluids. The swab of the present invention is particularly suited for obtaining samples for use in chemiluminescent assays for, among other analytes of interest, microbial contamination. Also disclosed is a polymeric disc for loading with reagent mixtures suitable for use in bioluminescent assay procedures. The reagent disc of the invention is characterized by high resistance to chemical and mechanical degradation. In addition, the disc has a high void volume and high absorptive capacity.

Abstract: Disclosed herein is a device and methods for the rapid chemiluminescence assay of surfaces to detect the presence of microbial contamination. The device and methods are suitable for use by untrained personnel under the relatively harsh and variable conditions found in the field, for example in fast food restaurants and other food preparation areas. The chemiluminescence reaction that is the source of the analytical signal in the disclosed assay device and method is preferably based on a luciferase/luciferin system. The method for sampling disclosed herein comprises the steps of pre-wetting the sampling swab to a level below that of absorptive saturation; wiping a surface to be sampled with the swab with sufficient pressure to expel the wetting solution onto the surface; and, after reducing the pressure exerted on the sampling swab, further wiping the surface to re-absorb the moisture from the surface.

Abstract: A hand-held assay device measuring chemiluminescence generated by as ample of ATP or other entity capable of chemically reacting to generate photoluminescence includes a photodiode detecting light which is emitted from the sample to produce a sample signal, another photodiode generating a reference signal in response to environmental changes, switched integrators amplifying the sensor signal over a controllable integration time to detect an output signal indicative of the presence of the sample.

Abstract: The optical measurement signals in a flame atomic absorption spectrophotometer are first amplified in a substantially linear variable gain amplifier. The gain of the variable gain amplifier is adjusted to provide a predetermined magnitude of output signal during a calibration phase of the spectrophotometer. The resultant output signals from the variable gain amplifier are then converted to a logarithmic function in a logarithmic amplifier during optical absorption measurements.

Abstract: The circuit includes an inverter to be connected to a source of d.c. power. The inverter has a transformer with a center-tapped primary winding. Separate controllable switching devices are connected to the respective ends of the primary winding. Both switching devices are arranged to be connected in common to one output terminal of the d.c. power source. The center tap of the transformer primary winding is arranged for connection to the other output terminal of the d.c. power source. The transformer has a laminated silicon steel core, and includes a secondary winding arranged for connection across the input terminals of a gaseous discharge lamp. A control circuit is connected to control conduction by the separate controllable switching devices in alternating sequence at a desired frequency of operation.

Abstract: The interlock assures that the end of a drain trap entrance pipe is covered with liquid. The system includes a control circuit with a circuit element which changes impedance with temperature changes. The circuit element is arranged to be thermally coupled with the drain trap liquid when the discharge end of the drain trap entrance pipe is immersed in the liquid. The circuit applies a current to the circuit element to thereby apply energy thereto. The circuit element achieves a lower steady-state temperature when thermally coupled with the liquid. The control circuit is operable to detect the difference in resistance when the circuit element is at the lower temperature. The control circuit is connected to a valve device for controlling combustion gas for the spectrophotometer and is operable to enable the valve device to enable the spectrophotometer when the circuit element is at the lower temperature and to disable the spectrophotometer at a higher temperature.