Robert S Ray

42185351, Aug 19, 1980

Dec 7, 1978

5/967324

Robert A. Ray - Fullerton CA

Beckman Instruments, Inc. - Fullerton CA

G01N 3114
C07G 702

435 12

An enzymatic reagent is provided for use in the kinetic measurement of the concentration of an enzyme substrate present in a sample and possessing the Michaelis-Menten relationship between reaction rate and substrate concentration. The reagent includes an enzyme such as glucose oxidase, uricase or urease for reacting with corresponding enzyme substrates such as glucose, uric acid or urea. In addition, the reagent includes a nonreacting competitive inhibitor of the enzyme. The inhibitor is present in an amount sufficient to improve the linearity of the reaction rate-concentration relationship associated with the enzyme substrate reaction at concentrations which are low relative to the Michaelis-Menten constant, Km, for the particular enzyme substrate reaction. The improved linearity, in turn, improves the accuracy of the kinetic measurements of substrate concentration made by linear output analyzers especially in an upper portion of the predetermined range where the relationship is particularly nonlinear.

40860612, Apr 25, 1978

Feb 28, 1977

5/772410

Jack L. Hoffa - Brea CA
Robert A. Ray - Fullerton CA

Beckman Instruments, Inc. - Fullerton CA

G01N 3316
G01N 114

23259

Apparatus for the analysis of samples such as blood or urine includes a reaction cell for reacting the sample with a chemical reagent at a predetermined temperature. A heat exchanger is provided on the reaction cell for establishing the temperature of the cell. Reagent is pumped into the cell through a conduit, and a portion of the conduit is wound around the reaction cell in contact with the heat exchanger to preheat reagent in the conduit before the reagent is pumped into the cell.