A lateral flow method for the determination of an analyte in a sample utilizes
biospecific affinity reactions. The method comprises forming a complex comprising
Reactant I - - - Analyte - - - Reactant* wherein Reactant* and Reactant
I exhibit biospecific affinity to the analyte, Reactant* is analytically detectable,
and Analyte is the analyte or an analyte-related reactant, determining
a detectable signal from Reactant* in the complex (sample value), and obtaining
the amount of analyte in a sample by comparing the sample value with one or more
calibrator values, each of which corresponds to a standard amount of analyte. Before
determination of the calibrator value, either calibrator or a binder for the calibrator
has been bound to a matrix and is released at the determination of calibrator value.
The calibrator and the analyte have the ability to biospecifically bind to Reactant*
via equivalent binding sites, and one or more calibrator zones comprising calibrator
or binder for the calibrator are located in the same process flow as Reactant I
in a detection zone. A device for transforming measured signal values for a completed,
analytically detectable reactant (Reactant*) to real amounts of analyte in a sample
comprises a flow matrix in which there is an area of process flow for the transport
of Reactant*, having one or more calibrator zones, an application zone for Reactant*
upstream of the one or more calibrator zones, and one or more detection zones downstream
of the one or more calibrator zones.
