Patent ID: 6489133
Filing Date: 2002-12-03
Classification: C12Q,G01N,Y02A,Y10S,Y10T

Abstract:
An apparatus for measuring the concentration of glucose in a sample of whole blood, which comprises:(a) a chamber for removably accepting a test strip that includes a porous matrix pad which (1) has a first major surface for accepting the sample and a reflective second major surface opposite to the first surface, (2) allows a portion of the sample to travel through the pad from the first surface toward the second surface, and (3) is impregnated with a reagent that reacts with glucose to cause a change in the reflectance at the second surface; (b) means for illuminating the second surface of the pad in the chamber; (c) means for monitoring intensity of light reflected from the second surface of the pad in the chamber; (d) means for taking a sequence of reflectance readings from the second surface of said matrix at specified time intervals upon detecting a predetermined drop in reflectance sufficient to indicate that said sample has reached said first surface; and (e) means for calculating said glucose concentration in said sample from one of said reflectance readings upon detection of a suitably stable endpoint, without having determined the time at which sample was initially applied to the matrix pad.