Abstract: A multilayer test strip and method of using the test strip for determining concentration of HDL cholesterol in a whole blood sample. The inventive test strip includes a two-stage blood separation mechanism, including a first glass fiber matrix which separates most of the blood cells and an adjacent, second matrix preferably also containing glass fibers that separates the remainder of the blood cells. The second layer also precipates and retains non-HDL cholesterol, thereby providing plasma that is substantially free of red blood cells and substantially free of non-HDL cholesterol to a reaction layer. Precipitation and retention on non-HDLs takes place by a vertical or dead-end filtration in a single layer. The reaction layer produces a color, the intensity of which is proportional to the concentration of HDL cholesterol in the blood sample which is applied to the test strip.

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: A multilayer test strip and method of using the test strip for determining concentration of HDL cholesterol in a whole blood sample. The inventive test strip includes a two-stage blood separation mechanism, including a first glass fiber matrix which separates most of the blood cells and an adjacent, second matrix preferably also containing glass fibers that separates the remainder of the blood cells. The second layer also precipates and retains non-HDL cholesterol, thereby providing plasma that is substantially free of red blood cells and substantially free of non-HDL cholesterol to a reaction layer. Precipitation and retention on non-HDLs takes place by a vertical or dead-end filtration in a single layer. The reaction layer produces a color, the intensity of which is proportional to the concentration of HDL cholesterol in the blood sample which is applied to the test strip.