Affinity reagents having enhanced binding and detection characteristics

A detectable probe, comprising:

• (a) a retaining component, wherein the retaining component comprises a first face and a second face, wherein the first face is offset from the second face;
• (b) a plurality of binding components, wherein the plurality of binding components is attached to the first face;
• and
• (c) a plurality of detectable labels, wherein the plurality of detectable labels is attached to the second face.

A method of detecting a polypeptide, comprising:

• (a) contacting a detectable probe to a solid support, wherein a polypeptide is immobilized at an address on the solid support, wherein the detectable probe comprises:
• (i) a retaining component, wherein the retaining component comprises a first face and a second face, wherein the first face is offset from the second face;
• (ii) a plurality of binding components, wherein the plurality of binding components is attached to the first face;
• and
• (iii) a plurality of detectable labels, wherein the plurality of detectable labels is attached to the second face;
• (b) coupling a binding component of the plurality of binding components of the detectable probe to the polypeptide immobilized on the solid support;
• and
• (c) detecting a signal from a detectable label of the plurality of detectable labels of the detectable probe at the address of the solid support.

An array composition, comprising:

• (a) a solid support comprising a plurality of sites;
• (b) a plurality of differing polypeptides attached to the plurality of sites, wherein each site of the plurality of sites is attached to only one polypeptide of the plurality of differing polypeptides;
• and
• (c) a plurality of detectable probes bound to differing polypeptides of the plurality of differing polypeptides, wherein each detectable probe of the plurality of detectable probes is substantially identical, and wherein each detectable probe of the plurality of detectable probes comprises:
• (i) a retaining component, wherein the retaining component comprises a first face and a second face, wherein the first face is offset from the second face;
• (ii) a plurality of binding components, wherein the plurality of binding components is attached to the first face;
• and
• (iii) a plurality of detectable labels, wherein the plurality of detectable labels is attached to the second face.