Abstract: A light generating dry disposable device for determining the presence of analytes in a test sample is disclosed. The device comprises a first zone containing conjugated ligand which is capable of reacting with analytes in the test sample. The ligand is conjugated with a photoprotein or related enzyme. The device further comprises a second trapping zone comprising immobilized analyte. The device also includes a third zone containing a reporter system that activates light generation by the conjugate. The conjugates are maintained in the first zone such that they are removable from the first zone when reacted with the soluble analytes from the test sample passing through the first zone, but not removed from the second trapping zone in the absence of such analytes. The third zone contains material capable of reacting with the photoprotein- or enzyme-linked ligand to produce a light-emitting reaction which indicates the presence of the analyte being tested. The present invention provides dry flow through zones.