Abstract: A method for filtrating liquid sample such as blood or the like with a filter member utilizing inner vacuum, the same enabling completion of filtration without removing a stopper, and superior in safety and being free from contamination. In collecting and filtrating the liquid sample using a sample collection vessel 1, in which a sample-collecting part 3 containing a filter member 4 is inserted in a vacuumed sample-storing part 2, the sample storing part 2 and sample-collecting part 3 are air-tightly sealed with a stopper 5, the liquid sample such as blood or the like collected in the sample-collecting part 3 is filtrated by the filter member 4. When the filtration stops, a hollow needle 12 is pierced through the stopper 5 and thus the sample-collecting part 3 is communicated with atmosphere, thereby the pressure in the sample-collecting part 3 being enhanced upper than in atmosphere to enable the filtration again.

Abstract: An object of the invention is to achieve an increased speed of blood collection and separation as well as ease of handling of plasma components after blood separation. A blood-collecting tube, which draws in blood and separates it by using an internal negative pressure in the tube, comprises an upstream tube 10 having a blood inlet 11 and blood outlets 18, a filter 20 for separating blood and a downstream tube 12. A plug 18 is fitted to the blood inlet 11 to thereby close the interior of the upstream tube 10, and the filter 20 is installed so that it blocks the blood outlets 18. The downstream tube 12 is disposed to enclose the filter 20 and constructed in such a way that the downstream tube 12 can be attached to and detached from the upstream tube 10.