ASSAY DEVICE AND IMMUNOASSAY

摘要

This invention relates to an improved assay device and assay for detecting or quantitating the presence or absence of a substance in a sample. The device has multiple layers comprising a permeable layer (a) having a capture reagent attached to less than the entire membrane, a selectively permeable layer (b) which does not allow assay reagents to pass through (b) and an absorbent layer (c). Layer (b) is in communication with layers (a) and (c). Layer (b) has at least one hole extending therethrough and the hole or holes are directly below the capture reagent in layer (a). The area of the hole or the combined area of the holes is less than the area covered by the capture reagent. This invention also relates to a method of reducing background color development in an absorbent layer of an assay device.