Abstract: Apparatus for determining concentration of creatinine in whole blood or plasma using a 1-methylhydantoinase (NMHase) catalyzed reaction, wherein the invention uses commercially available NMHase and thus eliminates prior art stabilization procedures for NMHase. Conveniently, known Trinder reagents and oxidative couplers are used for the indicator system. It has been found that by judiciously selecting the reagents used for the indicator system and/or varying the amount of enzyme NMHase that is loaded into the assay, the effect of the blank reaction can be minimized in the dynamic range of interest such that concentration of creatinine in normal and pathological levels can be measured directly without having to adjust for a blank reaction caused by bound N-methylhydantoin (NMH).

Abstract: A method for determining concentration of creatinine in whole blood or plasma using a 1-methylhydantoinase (NMHase) catalyzed reaction, wherein the invention uses commercially available NMHase and thus eliminates prior art stabilization procedures for NMHase. Conveniently, known Trinder reagents and oxidative couplers are used for the indicator system. It has been found that by judiciously selecting the reagents used for the indicator system and/or varying the amount of enzyme NMHase that is loaded into the assay; the effect of the blank reaction can be minimized in the dynamic range of interest such that concentration of creatinine in normal and pathological levels can be measured directly without having to adjust for a blank reaction caused by bound N-methylhydantoin(NMH).

Abstract: Apparatus and method for determining concentration of creatinine in whole blood or plasma using a 1-methylhydantoinase (NMHase) catalyzed reaction, wherein the (NMHase) used in the reaction has its own substrate, NMH, bound thereto. The present invention uses commercially available NMHase and thus eliminates prior art stabilization procedures for NMHase. Conveniently, known Trinder reagents and oxidative couplers are used for the indicator system. It has been found that by judiciously selecting the reagents used for the indicator system and/or varying the amount of enzyme NMHase that is loaded into the assay, the effect of the blank reaction can be minimized in the dynamic range of interest such that concentration of creatinine in normal and pathological levels can be measured directly without having to adjust for a blank reaction caused by bound NMH.

Abstract: A dry phase test strip (20) and method are provided for determining the concentration of LDL in whole blood or plasma. The inventive test strip (20) includes one stack (92) or panel that measures concentration of total cholesterol and another stack (94) or panel that measures concentration of the sum total of HDL, VLDL and chylomicrons (“non-LDLs”). The difference between the values just noted is equal to the concentration of LDL cholesterol. Dry phase test strips (20) of the present invention function at room temperature and all test results are produced from pseudo-endpoint reflectance measurements such that the test method need not be timed. Also disclosed is the capability for an improved lipid panel that provides concentration in a blood sample of HDL, total cholesterol and LDL cholesterol without relying upon the Friedewald equation.