Linear microarrays

A device for detecting a plurality of biomolecular probes in a sample, said device comprising a vessel comprising:

• (a) a casing having an inner surface and input and output openings,
• (b) a nonporous substrate having an outer surface and contained within said casing,
• (c) a liquid sample comprising biomolecular probes and contained within said casing,
• wherein the substrate outer surface contains a plurality of regions arranged in a defined manner and each of said regions has a different one of a plurality of immobilized specific binding targets which specifically bind a corresponding one of the plurality of the biomolecular probes, and said substrate outer surface is in close proximity with the inner surface of said casing so as to minimize the ratio of the liquid sample volume contained within said casing to the substrate outer surface area, yet permit flow of the liquid sample from the input opening, between the substrate outer surface and the casing inner surface, and to the output opening,
• wherein the device is adapted for differential gene expression analysis, wherein the immobilized binding targets and corresponding biomolecular probes comprise polynucleotides which specifically bind by hybridization, and wherein the probes comprise two sets, wherein the probes of each set are derived from a different sample source and comprise a different label.