Patent ID: 7087397

Claim:
A method of determining concentration of HDL cholesterol in a whole blood sample containing non-HDL cholesterol, said method comprising: a) providing a test strip holder and a test strip; said test strip holder including an application window and a rest reading window, said windows comprising vertically aligned openings in said holder; said test strip comprising a layered stack comprising a red blood cell separation layer, a non-HDL separation chemistry layer, and an HDL reaction layer; said non-HDL cholesterol separation chemistry layer containing non-HDL cholesterol separation chemicals for separating the non-HDL blood components from the HDL blood components so that the non-HDL components do not participate in the reaction in said HDL reaction layer; said HDL reaction layer containing chemicals for reacting with said HDL, said layers arranged in a vertical stack with said HDL reaction layer at the bottom of said stack; said test strip located in said test strip holder between said windows, with said reaction layer adjacent said test reading window; b) applying blood to the top of said stack through said application window and permitting fluid from said blood to flow vertically downward in said stack to said HDL reaction layer without substantial lateral migration of fluid below said red blood cell separation layer; c) separating said red blood cells from a fluid portion of said blood; d) separating said non-HDL cholesterol from said HDL cholesterol with said non-HDL cholesterol separation chemicals; e) reacting said HDL with said chemicals in said HDL reaction layer; and f) reading a property of said reaction layer through said reading window to determine said concentration of HDL cholesterol.