Method for producing a microtiter plate

摘要

A well-less filtration device comprising a plurality of preformed filter means, wherein said device comprises a laminate of a pre-filter layer and a porous support layer with a solid phase extraction medium there between, said pre-filter layer and porous support layer being ultrasonically welded together at the complete periphery of each preformed filter means, wherein the preformed filter means comprises solid phase extraction medium enclosed between the pre-filter layer and porous support layer and wherein land areas are defined between preformed filter means.