| abstract |
An assay device having a liquid flow path, flow of liquid along the flow path being initially impeded by a flow block comprising a substance which is suspendable or soluble in the liquid, such that contact of the flow block with the liquid suspends or dissolves at least part of the flow block over a period of time, so as subsequently to permit the liquid to flow along the flow path with less impedance. The flow block may be a hydrophilic substance and may comprise a peptide, saccharide eg sucrose, albumen. The assay device may be a lateral flow device. |