An apparatus for processing biological sample, comprising: at least one semi-permeable column, wherein the inner portion of which defines a first receiving space, the bottom of the first receiving space has at least one semi-permeable membrane, the top portion of the semi-permeable column has a first opening and a first flange extending radially and outwardly from the first opening, and the bottom of the semi-permeable column has a first outlet; at least one adaptor column, wherein the interior of which defines a second receiving space, the top portion of which has a second opening and a second flange extending radially and outwardly from the second opening, the bottom portion of which has a second outlet protruding downwardly, the diameter of the second receiving space is slightly larger than the outer diameter of the semi-permeable column such that the semi-permeable column can be inserted into the adaptor column and be loosely received in the second receiving space of the adaptor column, the second flange having a second sealing element fitting therearound such that when the semi-permeable is inserted into the adaptor column, the first flange will rest on the second sealing element; a vacuum manifold, comprising: a base, the interior of which defines a receiving space; and a lid covering the base, comprising at least one slot, wherein the internal diameter of which is slightly larger than the outer diameter of the adaptor column such that the adaptor column is loosely received in the slot of the vacuum manifold, and the slot forms a through hole at the bottom thereof for communicating with the receiving space of the base; at least one sealing element (125") is positioned at the bottom of the slot, and each of the sealing elements having an opening at its center, whereby when the adaptor column is inserted into the opening at the center of the sealing element, it can be secured in position, and when vacuum is applied to the vacuum manifold, air would not pass through between the second outlet and the sealing element, nor through between the first flange and the second sealing element. at least one semi-permeable column, wherein the inner portion of which defines a first receiving space, the bottom of the first receiving space has at least one semi-permeable membrane, the top portion of the semi-permeable column has a first opening and a first flange extending radially and outwardly from the first opening, and the bottom of the semi-permeable column has a first outlet; at least one adaptor column, wherein the interior of which defines a second receiving space, the top portion of which has a second opening and a second flange extending radially and outwardly from the second opening, the bottom portion of which has a second outlet protruding downwardly, the diameter of the second receiving space is slightly larger than the outer diameter of the semi-permeable column such that the semi-permeable column can be inserted into the adaptor column and be loosely received in the second receiving space of the adaptor column, the second flange having a second sealing element fitting therearound such that when the semi-permeable is inserted into the adaptor column, the first flange will rest on the second sealing element; a vacuum manifold, comprising: a base, the interior of which defines a receiving space; and a lid covering the base, comprising at least one slot, wherein the internal diameter of which is slightly larger than the outer diameter of the adaptor column such that the adaptor column is loosely received in the slot of the vacuum manifold, and the slot forms a through hole at the bottom thereof for communicating with the receiving space of the base; a base, the interior of which defines a receiving space; and a lid covering the base, comprising at least one slot, wherein the internal diameter of which is slightly larger than the outer diameter of the adaptor column such that the adaptor column is loosely received in the slot of the vacuum manifold, and the slot forms a through hole at the bottom thereof for communicating with the receiving space of the base; at least one sealing element (125") is positioned at the bottom of the slot, and each of the sealing elements having an opening at its center, whereby when the adaptor column is inserted into the opening at the center of the sealing element, it can be secured in position, and when vacuum is applied to the vacuum manifold, air would not pass through between the second outlet and the sealing element, nor through between the first flange and the second sealing element.