| 摘要 |
New method of inserting a filter into a blood sample tube. The blood is centrifuged or sedimented into two phases: serum or plasma (3); and residual red blood cell cake (2). A boundary layer formed between the phases is reinforced by a partition layer (gel, 6) and/or a solid partition. A filter (13) and reception vessel (14) are inserted into the sample tube (1) and forced in by an actuator (11), to a set position. This is determined by a pressure rise, which occurs as the boundary layer is reached, during the descent of the actuator. Alternatively or in addition, it is stopped on reaching a required reception vessel filling level. The return path is blocked. In each case an air cushion is maintained between the surface of the serum or plasma level in the reception vessel, and the lower edge of the actuator. |
