Abstract: Highly sensitive devices for detecting nitric oxide and/or other gaseous analytes in gaseous samples are improved by the incorporation of a carbon monoxide scavenger in the interior of the device or in the device packaging. The release of carbon monoxide within the housing of the device by the plastic used in the construction of the housing or by anything within the device that releases carbon monoxide causes a loss in sensitivity due to competition between the carbon monoxide and the nitric oxide for the binding sites on the device sensor. The scavenger corrects this by either catalyzing the oxidation of carbon monoxide to the less competitive carbon dioxide or immobilizing the carbon monoxide by affinity-type or covalent binding. Analogous effects are achieved for analytes other than nitric oxide but that likewise encounter interference from carbon monoxide in binding to sensors.

Abstract: The present invention is a system and method of conditioning the sample and surrounding environment of an exhaled breath sensor. It includes (i) using a particular molecular sieve for a triple purpose: (a) maintaining the sensor at a constant relative humidity during storage, (b) equilibrating the incoming breath stream to the same relative humidity as the sensor, and (c) eliminating the analyte from the environment around the sensor during storage. The present invention also includes removal of interfering components from the exhaled breath, such as carbon dioxide, as well as a thermal management technique.

Abstract: Highly sensitive devices for detecting nitric oxide and/or other gaseous analytes in gaseous samples are improved by the incorporation of a carbon monoxide scavenger in the interior of the device or in the device packaging. The release of carbon monoxide within the housing of the device by the plastic used in the construction of the housing or by anything within the device that releases carbon monoxide causes a loss in sensitivity due to competition between the carbon monoxide and the nitric oxide for the binding sites on the device sensor. The scavenger corrects this by either catalyzing the oxidation of carbon monoxide to the less competitive carbon dioxide or immobilizing the carbon monoxide by affinity-type or covalent binding. Analogous effects are achieved for analytes other than nitric oxide but that likewise encounter interference from carbon monoxide in binding to sensors.

Abstract: The flow rate of a gaseous sample of exhaled breath through an analytical device is controlled by a pump, and in certain embodiments two pumps. Placement of the analyte sensor in a secondary stream branching off of the primary stream through the device offers further control over the manner, duration, and quantity of the breath that is placed in contact with the sensor.

Abstract: The degradation over time that is commonly seen with analyte-binding proteins when used as sensors for trace amounts of an analyte in a gaseous mixture is reduced by maintaining the sensor in a low-oxygen or oxygen-free environment.

Abstract: A gas analysis sensing element and a method of making the sensing element are disclosed. In one embodiment, the sensing element includes cytochrome c embedded in a sol-gel matrix. The sol-gel matrix is either a thin film or a monolith. Parameters for creating such a sensing element, including protein concentration, sol-gel pore size, surface area for the monolith embodiment, sol-gel components, and processing temperature, are also disclosed.