The present invention relates to a lateral flow
assay and
system, including a test strip, for detection and quantification of analytes in samples, such as samples containing cells and fluid, where the
assay is volume independent, and the sample size is less than about 100 μl, where the test strip includes a first membrane such as a sample filter, that is in capillary contact with an optional second membrane, such as a fluid collector, the second membrane, if present is in capillary contact with an optional third membrane, such as a conjugate pad containing a mobilizable detectable agent, or with a fourth membrane, which is a chromatographic strip, which optionally contains a mobilizable detectable agent, all such membranes being in fluid contact with a fifth membrane, such as a buffer pad, a sixth membrane, such as an absorbent pad, optionally a seventh membrane, which is also an absorbent pad, a capture band for capturing the
analyte and at least one control band, or alternatively, the chromatographic strip contains the mobilizable detectable agent in place of a conjugate pad, where the test strip is configured to
support removal of red blood cells from the sample and to allow uni-directional or bi-directional fluid flow of fluid from the sample filter to the capture band to be retained therein and detected thereon.