Diagnostic devices and apparatus for the controlled movement of reagents without membranes

An analytical device for determining a presence or amount of a ligand in a test sample, said device comprising:

• an inlet port and a vent;
• one or more channels;
• an array of texture structures in fluid communication with at least one channel, each texture structure having a surface comprising an immobilized receptor covalently or non-covalently attached to said surface of said texture structure, said receptor capable of binding a ligand, whereby when said test sample containing a ligand flows through said channel(s), said ligand diffuses across the width of said channel(s) to bind said receptor immobilized on said texture structure;
• and,
• a labeled reagent comprising a specific binding member conjugated to a detectable label, said labeled reagent capable of producing a signal at said receptor immobilized on said texture structure to indicate the presence or amount of a ligand in a test sample.

An assay device comprising:

• a sample addition reservoir;
• a sample reaction barrier fluidly connected to said sample addition reservoir;
• a reaction chamber fluidly connected to said sample reaction barrier, said chamber having at least two fingers in walls thereof, wherein said barrier has a higher capillarity than said reaction chamber;
• a time gate fluidly connected to the reaction chamber, said time gate capable of permitting fluid to pass therethrough at a desire d flow rate;
• a diagnostic element fluidly connected to the time gate, said diagnostic element comprising an array of texture structures capable of immobilizing at least one conjugate in at least one zone;
• and,
• a used reagent reservoir fluidly connected to said diagnostic element, whereby fluid can flow in sequence from said sample addition reservoir, to said barrier, to said reaction chamber, to said time gate, to said diagnostic element then to said used reagent reservoir.