Abstract: A chromatographic assay device for use with immunoassays allows rapid and convenient assays of analytes of biological interest, and permits extractions to be carried out in situ, avoiding the use of separate extraction vessels. The device has a wide dynamic range and avoids interference from particulates or colored components. In one form, the device comprises: (1) a first opposable component comprising a sample preparation means adapted to receive a sample to be assayed; and (2) a second opposable component comprising a chromatographic medium. The first and second opposable components can be brought into opposition so as to cause the sample preparation means to apply the sample to be tested to the chromatographic medium. Preferably, the analyte is detected with a visually detectable label. Other variations of the device vary the arrangement of components to provide optimal chromatography for a variety of analytes, as well as to permit bidirectional chromatography.

Abstract: A chromatographic assay device for use with immunoassays allows rapid and convenient assays of analytes of biological interest, and permits extractions to be carried out in situ, avoiding the use of separate extraction vessels. The device has a wide dynamic range and avoids interference from particulates or colored components. In one form, the device comprises: (1) a first opposable component comprising a sample preparation means adapted to receive a sample to be assayed; and (2) a second opposable component comprising a chromatographic medium. The first and second opposable components can be brought into opposition so as to cause the sample preparation means to apply the sample to be tested to the chromatographic medium. Preferably, the analyte is detected with a visually detectable label. Other variations of the device vary the arrangement of components to provide optimal chromatography for a variety of analytes, as well as to permit bi-directional chromatography.