An analytical test device useful for example in pregnancy testing,
comprises a hollow casing (500) constructed of moisture-impervious solid
material, such as plastics materials, containing a dry porous carrier
(510) which communicates indirectly with the exterior of the casing via a
bibulous sample receiving member (506) which protrudes from the casing
such that a liquid test sample can be applied to the receiving member and
permeate therefrom to the porous carrier, the carrier containing in a
first zone a labelled specific binding reagent is freely mobile within
the porous carrier when in the moist state, and in a second zone
spatially distinct from the first zone unlabelled specific binding
reagent for the same analyte which unlabelled reagent is permanently
immobilised on the carrier material and is therefore not mobile in the
moist state, the two zones being arranged such that liquid sample applied
to the porous carrier can permeate via the first zone into the second
zone, and the device incorporating means, such as an aperture (508) in
the casing, enabling the extent (if any) to which the labelled reagent
becomes bound in the second zone to be observed. Preferably the device
includes a removable cap for the protruding bibulous member.