System for separating bodily fluid constituents and method for producing such a system

A system for separating bodily fluid constituents, comprising:

• a first substrate which, in a first main surface, has a first cavity configured to hold a bodily fluid sample;
• a second substrate which, in a first main surface facing the first substrate, has a second cavity configured to hold constituents separated from the bodily fluid sample, wherein the second cavity lies opposite to the first cavity;
• a filter layer which is arranged between the first substrate and the second substrate and which is configured to separate constituents of the bodily fluid sample in the first cavity and to pass the separated constituents to the second cavity;
• and
• a first thermoplastic connection layer which is interposed between the first substrate and the filter layer, the first thermoplastic connection layer being connected to both the first main surface and the filter layer,
• wherein the first thermoplastic connection layer is configured to interconnect the first main surface of the first substrate and the filter layer in a fluid-tight manner,
• wherein the first thermoplastic connection layer has a cutout lying opposite to the first cavity,
• wherein the first substrate comprises a first microchannel which is connected to the first cavity and which is configured to be actuated with overpressure such that the bodily fluid sample situated in the first cavity is pressed out of the first cavity through the filter layer,
• wherein the second substrate comprises a first pressure channel on the first main surface, which pressure channel adjoins a main surface of the thermoplastic connection layer,
• wherein the first microchannel adjoins the opposing main surface of the first thermoplastic connection layer, and
• wherein the first pressure channel is configured to be actuated with overpressure such that the first thermoplastic connection layer penetrates into the first microchannel under elastic deformation and produces a corresponding overpressure in the first microchannel.