Puritan-bennett Corporation

Quidel Corporation

Alan M Nelson

Henry K Hui

Charles S Bankert

Soonkap Hahn

Monte Bennett

Allan D Pronovost

Jan W Pawlak

Carmen L Soikowski

Samuel D Riccitelli

Jeffrey T Jackson

Thomas A Shern

Richard Homick

One-step enzyme immunoassays in which enzyme-antibody conjugate or label and enzyme substrate are separated until separation of bound and free enzyme conjugate or label is complete. This separation is accomplished by using variable flow paths, immobilization of substrate at the test line, placement of substrate in a sac or association with a particle label, enzyme product chemical capture, delay zone dissolution and protected enzyme substrates.

Enzyme substrate delivery and product registration in one step enzyme immunoassays

The carbon dioxide sensor includes a CO.sub.2 sensing matrix formed from a hydrophilic, gas permeable, cross-linked polyurethane. The polyurethane matrix is formed from a polyurethane pre-polymer mixture which cross links when mixed with an aqueous carbon dioxide buffer solution. The dye-buffer solution is physically entrapped as a homogeneous dispersion in the polymer matrix. The matrix is applied to the exposed glass core of an optical fiber, which may first be coated with a primer to allow the polyurethane matrix to bond firmly to the tip of the optical fiber. The hydrophilic polymeric matrix is preferably coated with a hydrophobic material to help avoid leaching of the dye from the matrix, and to prevent diffusion of hydronium ions into the sensing matrix. The hydrophobic polymer overcoat may thereafter be cured by heat treatment. The hydrophobic coating may also contain a light reflective material such as TiO.sub.2.

CO.sub.2 sensor using a hydrophilic polyurethane matrix and process for

The method for making an optical fiber microsensor involves applying an uncured analyte sensing matrix to an optical fiber and crosslinking the sensing matrix in situ on the optical fiber to yield an ion permeable microsensor which can be used intravascularly to monitor pH, or partial pressures of oxygen or carbon dioxide in blood. The liquid form of the sensing matrix contains a crosslinking agent and a crosslinking inhibitor which can be removed by exposure to elevated temperatures to allow the sensing matrix to crosslink and cure as desired, in situ, on the surface of the optical fiber. A liquid crosslinking overcoat layer containing a crosslinking agent and a crosslinking inhibitor which can be removed by exposure to heat can also be applied over the cured sensing matrix.

Method and compositions for manufacture of chemical sensors

The optical fiber microsensor includes an optical fiber having a portion of the surface of a light conducting core covered with a layer containing an analyte sensitive dye material. The dye indicator material is covalently bonded to a copolymer which is covalently bonded to a blocked polyether polyisocyanate. The resulting polymer is covalently bonded to the optical fiber core to prevent leaching of the indicator dye material during extended use.

Microsensor copolymer and method of manufacture

The method of stabilizing a carbon dioxide sensor involves formulation of a bicarbonate buffer solution in the sensor with a bicarbonate ion concentration of from about 100 mM to about 200 mM bicarbonate. The method also involves treatment of the sensor to reduce the instability that may occur in carbon dioxide sensors when such sensors are exposed to either very low or very high carbon dioxide levels for extended periods of time. The sensor is treated by exposing the sensor to an aqueous solution containing at least 2 weight percent carbon dioxide, for from several days to several months. The solution may be prepared in advance, or may be dynamically infused with carbon dioxide to provide the desired carbon dioxide content.

Method of stabilizing a carbon dioxide sensor

The method of stabilizing a carbon dioxide sensor involves treatment of the sensor to reduce the instability that may occur in carbon dioxide sensors when such sensors are exposed to either very low or very high carbon dioxide levels for extended periods of time. This is accomplished by storing the sensor in an aqueous solution containing at least 2 weight percent carbon dioxide, for from several days to several months. The solution may be prepared in advance, or may be dynamically infused with carbon dioxide to provide the desired carbon dioxide content.

The multiple optical fiber event sensor apparatus includes a semipermeable generally cylindrical shaft, one or more optical fiber gas sensor modules within the shaft, and an optical fiber pH sensor module extending beyond the distal end of the shaft, with the sensor modules arranged in an axially staggered relationship. The shaft contains a potting matrix for axially fixing the position of the optical fibers, and includes a gas permeable portion surrounding the one or more gas sensor modules, and a hydrophilic portion covering at least part of the pH sensor module. A hemodynamically shaped, rounded distal end is also provided on the distal end of the shaft. The device provides for a multiplicity of individual sensors incorporated in a single shaft which minimizes cross-interference and thrombus formation when used as an intravascular multi-sensor.

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San Diego, CA, United States of America

Alan M Nelson