Patent ID: 7220597
Filing Date: 2007-05-22
Classification: G01N

Abstract:
1. An assay test device for determining whether a fluid under test contains a certain substance, comprising: a housing having a top portion and a bottom portion; an elongated test strip disposed within said housing, said test strip containing a reagent and adapted to receive a sample of the fluid under test at a sample receiving end portion thereof; the elongated test strip including: an elongated printed circuit board attached to an inner surface of the housing extending substantially parallel to the test strip for mounting electronic components; a reaction sensor, an LED, and a sample sensor mounted side by side on one side of the printed circuit board opposite the intermediate portion of the porous carrier strip; the sample sensor mounted on said printed circuit board including a gap between the sample sensor and the test strip for detecting the presence of the sample as it flows from the test strip sample receiving end portion using the reflectance at a first position on the test strip for generating a signal indicative of the presence of said sample; a processor responsive to the sample presence signal for starting a timer to generate a time delay interval and for generating a time-out signal at the end of the interval; the reaction sensor mounted in said printed circuit board and responsive to said time-out signal for detecting the certain substance in the fluid under test received on said test strip using the reflectance at a second position on the test strip to generate an electrical signal indicative of the amount of the substance detected; said processor being responsive to said signal from said reaction sensor for generating an output signal indicative of the presence or absence of at least a predetermined quantity of the substance contained in the sample; and a display mounted on said housing responsive to said output signal for indicating the presence or absence of a predetermined quantity of the certain substance contained within the fluid under test, wherein the sample sensor is a photo-optic sensor.