Abstract: A test strip includes a body defining a sample entry, a test area, and a cavity. The cavity is configured to transport a test sample from the sample entry to the test area. The test strip includes at least one passive mixing element within the cavity. The passive mixing element is configured to cause passive mixing of the test sample as the test sample is carried from the sample entry toward the test area. A test sample to be analyzed is introduced to the sample entry and at least a portion of the test sample is transported through the cavity to the test area. During transport, the test sample is passively mixed.