Abstract: A precalibrated sensing system for determining a blood parameter such as the partial pressures of oxygen (pO.sub.2) and carbon dioxide (pCO.sub.2), and the negative logarithm of hydrogen ion activity (pH). A dry sensor is provided which may be calibrated in the factory, packaged, sterilized and stored, without requiring recalibration prior to use.

Abstract: An oxygen sensor is provided for determination of the partial pressure of oxygen. In one aspect, the invention consists of oxygen-quenchable luminescent lanthanide complexes for an oxygen sensor. The complexes are oxygen-quenchable even though immobilized in a solid matrix, such as a solid polymeric matrix, and preferably are terbium complexes of Schiff base or .beta.-diketone ligands. Certain preferred processes are described for improving the oxygen sensitivity of the lanthanide complexes. In another aspect, the invention consists of a combination measuring and reference analyte sensor containing both quenchable and nonquenchable luminescent materials. The materials luminesce at different wavelengths and thus may be transmitted together down a single optical fiber and later discriminated by means of filters and separtely detected. In a third aspect, the invention consists of a low-noise phosphorescent analyte sensor employing a gatable detector.

Abstract: Sensing apparatus for remote sensing of quantities such as blood oxygen concentration using a phosphorescent material located at one end of an optical fiber. The phosphorescent material emits a relatively long-lived luminescence when exposed to energy in a predetermined wavelength range. The sensing apparatus includes a light source for generating an incident pulsed energy signal within the predetermined wavelength range and a detector subsystem for selectively detecting the long-lived luminescence from the phosphorescent material. The light source and the detector subsystem are coupled to the other end of the optical fiber along a common optical path. The detector subsystem includes dual channels for detecting a measuring wavelength and a reference wavelength in the long-lived luminescence. The detector subsystem is inhibited during the incident pulsed energy signal to provide low noise operation. The detected signals are integrated and averaged to improve accuracy.

Abstract: An oxygen sensor is provided for determination of the partial pressure of oxygen. In one aspect, the invention consists of oxygen-quenchable luminescent lanthanide complexes for an oxygen sensor. The complexes are oxygen-quenchable even though immobilized in a solid matrix, such as a solid polymeric matrix, and preferably are terbium complexes of Schiff base or .beta.-diketone ligands. Certain preferred processes are described for improving the oxygen sensitivity of the lanthanide complexes. In another aspect, the invention consists of a combination measuring and reference analyte sensor containing both quenchable and nonquenchable luminescent materials. The materials luminesce at different wavelengths and thus may be transmitted together down a single optical fiber and later descriminated by means of filters and separately detected. In a third aspect, the invention consists of a low-noise phosphorescent analyte sensor employing a gatable detector.

Abstract: Apparatus and methods are provided for determining the concentration of a gaseous component in a fluid. A solid body of a natural or synthetic high polymer, which is permeable to the gaseous component, is exposed to the fluid, the polymer is exposed to infrared radiation, and the infrared absorption by the gas in the polymer is measured. In the preferred embodiment, a sensor is provided for making in vivo measurements of the concentration of CO.sub.2 in the blood. The sensor includes an optical fiber which is nonpermeable to CO.sub.2 and substantially transparent at the CO.sub.2 absorption wavelength range, and a solid body of polymeric material at the distal end of the fiber which is substantially transparent to the absorption wavelength range and permeable to CO.sub.2. An incident infrared signal is transmitted down the fiber, passes through the body, is reflected off the distal end of the body, and the intensity of the return signal is measured by a detector.