Patent ID: 8182766

Claim:
A multiwell filtration plate comprising: (A) a multiwell filtration plate having a top surface, a bottom surface and a plurality of circular filtration plate wells, each well having an open top, a bottom outlet, and one or more sidewalls forming an inner through bore; (B) a plurality of inserts, each insert located within the inner through bore of a different well, each insert having an upper surface, a lower surface, an open top, a bottom outlet, one or more sidewalls forming an inner through bore, and each insert inner through bore divided into a plurality of subassemblies, each subassembly includes a different liquid permeable material, wherein the pore size of each liquid permeable material decreases from the subassembly nearest the top of the insert to the subassembly nearest the bottom; and (C) an extension plate located above the filtration plate and sealed to the top surface of the plate, including a plurality of square extension plate wells having an open top, an open bottom outlet, and one or more sidewalls forming an inner through bore having an inwardly tapered surface near the bottom outlet, the extension plate wells are equal in number, corresponding in position, and located above the wells of the filtration plate.