Abstract: Provided herein is a method for processing a tissue sample. The method may comprise: (a) permeating the tissue section with monomers for a negatively charged expandible gel, (b) allowing the monomers to polymerize in the tissue sample, (c) hydrating the tissue sample, thereby causing the sample to expand, (d) adhering expanded tissue sample to a positively charged surface and (e) dehydrating the expanded tissue sample while it is on the planar surface.

Abstract: Provided herein, among other things, is a method for analyzing a sample. In some embodiments, the method makes use of a plurality of binding agents that are each linked to a different oligonucleotide, as well as a corresponding plurality of peroxidase-linked oligonucleotides, wherein each of the peroxidase-linked oligonucleotides specifically hybridizes with only one of the binding agent-linked oligonucleotides. In some embodiments the method may comprise labeling the sample with the plurality of binding agents en masse, and then staining the sample by hybridizing a single peroxidase-linked oligonucleotide with the sample to produce complexes that comprise the peroxidase and then treating the sample with at least one tyramide-label conjugate. The peroxidase in the complexes activates the conjugate and causes covalent binding of the label to the sample near the complexes. Reagents and kits for performing the method are also provided.