A chromatographic specific binding assay strip device, comprising: a
non-permeable platform strip; a permeable membrane testing strip
positioned on top of said non-permeable platform strip, with the testing
strip comprising at least one capture reagent site containing a capture
reagent for at least one specific analyte, a sample receiving pad
positioned on top of and at a proximal end of the non-permeable platform
strip, with the sample receiving pad having contact with a proximal end
of said permeable membrane testing strip, a reservoir pad positioned on
top of and at a distal end of said non-permeable membrane testing strip,
with the reservoir pad having contact with a proximal end of said
permeable membrane test strip; a supporting strip attached to and
extending from the proximal end of said non-permeable platform strip; and
a conjugate pad positioned on said supporting strip, said conjugate pad
comprising a semi-permeable membrane containing a colorant conjugate. The
semi-permeable membrane acts as a barrier between the conjugate pad and
the sample receiving pad, regulating the flow through the semi-permeable
membrane and overall flow of the assay by dipping the conjugate pad into
a sample solution, there will be increased binding between the analyte in
the sample and the conjugate (preferably colloidal gold), thereby giving
improved results on the lateral flow assay.