Reflux device for detection of analytes in samples

A device comprising:

• a. A sample-receiving port adjacent to a sample-collecting pad which is configured to allow a sample to be placed on the sample-collecting pad at a sample-collecting point;
• b. A detection zone which produces a signal in response to a sample analyte from the sample interacting with the detection zone, wherein the device is configured to cause the sample analyte to travel from the sample-collecting spot to the detection zone in a downstream direction;
• c. A first liquid reservoir placed in the downstream direction from the sample-receiving port and at a level above the sample-collecting pad, wherein said first liquid reservoir has a first liquid in a predetermined amount and the device is configured such that when the first liquid is released, the first liquid travels in an upstream direction, opposite to the downstream direction, to the sample-collecting point and then travels in the downstream direction after reaching the sample-collecting point;
• and
• d. A second liquid reservoir placed in the downstream direction from the first reservoir, wherein said second liquid reservoir has a second liquid and the device is configured such that when the second liquid is released, the second liquid travels in the downstream direction.