Patent ID: 8821812

Claim:
A device for handling a fluid to be assayed, said device comprising: a non-porous substrate having a substrate surface; at least one open fluid passage integrated into said substrate, said at least one fluid passage having a first end at which fluid is added to said device and a second end opposite said first end, said at least one open fluid passage being capable of supporting capillary flow; and at least one separate absorbing zone in fluid contact with said second end of said at least one open fluid passage, said at least one open fluid passage, including said at least one absorbing zone each comprising a plurality of projections substantially perpendicular to said substrate surface, said plurality of projections each having a height, diameter and a distance or distances between the projections, capable of generating capillary flow, lateral to said substrate surface, of a fluid added to the first end of said at least one open fluid passage and contacting said at least one absorbing zone in fluid contact with said second end of said at least one open fluid passage, and a foil directly placed on the top of the perpendicular projections of said at least one absorbing zone, said foil being solely and fully supported upon the projections and having hydrophilic properties to influence the flow velocity of fluid along said substrate surface from said first end to said second end of said open fluid passage and to accurately limit the fluid volume defined by said projections and in which said substrate, said at least one open fluid passage, and said at least one separate absorbing zone are made from the same material.