Patent ID: 7749388

Claim:
A filter column, comprising: a body having a passageway extending therethrough, the body having a first end, a second end and a longitudinal axis, an outer surface and an inner surface, a first body portion proximate to the first end, a third body portion proximate to the second end and configured to receive and retain a filter assembly comprising a retainer, a filter and a filter support, and a second body portion disposed between the first and third body portions; the outer surface having at least one bearing surface for seating on at least one collection tube; wherein the inner surface comprises at least one angled surface located proximate or above the at least one bearing surface that forms an angle with the longitudinal axis that is less than approximately 90 degrees; a filter disposed within the third body portion, the filter comprising a first side proximal to the first end and a second side proximal to the second end and defining a perimeter; a filter support disposed within the third body portion and contacting the second side of the filter and supporting the filter; and a retainer disposed within the third body portion and contacting the first side of the filter; the retainer having an outer edge, an inner edge, and an upper surface.