Profiling of biological analytes with spatially barcoded oligonucleotide arrays

A method of identifying a location of a protein in a tissue section, the method comprising:

• (a) contacting a plurality of analyte capture agents with the tissue section, wherein the tissue section is disposed on a substrate,
• wherein an analyte capture agent of the plurality of the analyte capture agents comprises:
• an analyte binding moiety that binds specifically to the protein,
• an analyte binding moiety barcode, and
• an analyte capture sequence that is substantially complementary to a capture domain, and
• wherein the substrate comprises a plurality of capture probes, wherein the plurality of capture probes comprise a spatial barcode and the capture domain that hybridizes to the analyte capture sequence;
• (b) extending the capture probe on the substrate using the analyte capture sequence as a template, thereby generating an extended capture probe on the substrate;
• (c) generating a complement of the extended capture probe on the substrate prior to the determining step;
• and
• (d) determining a sequence of (i) the spatial barcode or a complement thereof, and (ii) the analyte binding moiety barcode, or a complement thereof, and using the determined sequences of (i) and (ii) to identify the location of the protein in the tissue section.