Patent ID: 8580560

Claim:
A cap and filter step reduction tool assembly for use in separating product excreted externally of living cells from liquids, growth media and debris in which the product exists within a container, the container having a neck defining an opening to the container, the product having a size measured by molecular weight, comprising: a cap having a first portion configured to cover the opening of the container, an outlet and a filter assembly located therebetween, the filter assembly comprising: a filter housing having a porous support with a rim around a periphery of the porous support; a graded porosity filter fitting within that rim and having a small pore size sufficiently large to pass the product through the filter while retaining the debris; a locking ring urging a periphery of the filter against an outer portion of the filter; and a frit located to place the filter between the porous support and the frit, the frit being sealed to the housing so fluid flows through the frit and to the filter during use; a vent opening extending through the cap with a vent tube connected to the portion of the cap defining the vent opening, the vent tube having a length selected to extend into an ullage of the container when the container is inverted so product flows from the container through the filter and outlet of the cap.