Micro fluidic structures

An open micro fluidic system comprising:

• a substrate having a non-porous surface;
• a first plurality of microposts protruding from said non-porous surface of said substrate and defining at least one flow path in which liquid samples can be treated by desired procedures, wherein said at least one flow path is laid out for transport of liquid samples, wherein the at least one flow path extends in a lateral direction which is transverse to the protruding microposts;
• wherein cross sections of said microposts and the center to center spacing between each of the first plurality of microposts spontaneously induces a passive capillary action in a liquid sample applied to said at least one flow path, so as to force said liquid to move laterally away from where said liquid sample was applied, said first plurality of microposts further including at least one biological binder having an affinity to at least one component of a liquid sample introduced along said at least one flow path;
• a sample receiving area disposed prior to said at least one flow path and fluidly connected therewith;
• and
• a sample collecting sink disposed after said at least one flow path on said substrate and fluidly connected with said at least one flow path, said sample collecting sink having an area which is larger than the area of the at least one flow path extending from said sample receiving area, said sink having a second plurality of microposts protruding from said substrate surface, said second plurality of microposts having cross sections and center to center spacing between each of said microposts that further induce capillary flow from said flow path to said sample collecting sink and wherein of the cross sections and center to center spacing of said second plurality of microposts are different those than of said first plurality of microposts.