An in vitro test method for detecting at least one analyte of a sample liquid, wherein a device is used comprising two sample chambers, which are separated by a carrier having at least two surfaces, a front side of the carrier points towards the first sample chamber and a rear side of the carrier points towards the second sample chamber, and a) at least one receptor molecule is fixed on the front side of a carrier; b) at least one respective free volume is formed over the front side and rear side of the carrier and is delimited by a chamber wall; c) the first sample chamber has at least two openings, wherein a sample liquid flows through a first opening along a flow gradient over the front side of the carrier to the second opening spaced apart from the carrier; d) the second sample chamber has at least two openings, wherein the sample liquid flows through a first opening from the first sample chamber along a flow gradient over the rear side of the carrier and in a direction opposite the flow on the front side of the carrier to the second opening; e) the second opening of the first sample chamber and the first opening of the second sample chamber are interconnected by a channel, wherein this channel is smaller in diameter than the diameter of the sample chamber or of the free volume, and wherein the entire sample liquid flow runs between the two sample chambers through the channel between the sample chambers; f) the second opening of the second sample chamber enables the discharge of the liquid; g) the free volumes from b.) are formed at least partially with a liquid column, h) wherein the flow gradient along the front and rear sides of the carrier is provided by means of pressure application and entrains the liquid column from g.), wherein the at least one receptor molecule binds to at least one analyte from the sample liquid. a) at least one receptor molecule is fixed on the front side of a carrier; b) at least one respective free volume is formed over the front side and rear side of the carrier and is delimited by a chamber wall; c) the first sample chamber has at least two openings, wherein a sample liquid flows through a first opening along a flow gradient over the front side of the carrier to the second opening spaced apart from the carrier; d) the second sample chamber has at least two openings, wherein the sample liquid flows through a first opening from the first sample chamber along a flow gradient over the rear side of the carrier and in a direction opposite the flow on the front side of the carrier to the second opening; e) the second opening of the first sample chamber and the first opening of the second sample chamber are interconnected by a channel, wherein this channel is smaller in diameter than the diameter of the sample chamber or of the free volume, and wherein the entire sample liquid flow runs between the two sample chambers through the channel between the sample chambers; f) the second opening of the second sample chamber enables the discharge of the liquid; g) the free volumes from b.) are formed at least partially with a liquid column, h) wherein the flow gradient along the front and rear sides of the carrier is provided by means of pressure application and entrains the liquid column from g.), wherein the at least one receptor molecule binds to at least one analyte from the sample liquid. <EOS>