A multi-part device for separating plasma from whole blood is provided, with a sample taking unit for receiving whole blood, a filter unit with a layered filter with multiple layers for extracting plasma, and a pumping unit, typically a plunger pump, for creating a partial vacuum in the filter unit. The filter unit and a plasma collector vessel with a conical tip extending towards the filter unit are contained in a filter cartridge, which may be taken apart after plasma extraction, thus exposing the conical tip of the plasma collector vessel for sample input into an analyzer.