Seeing Molecules: Specificity

Correct detection depends on specificity—detecting only the target molecule. To achieve specificity, scientists rely on detector molecules that bind only to the target molecules, not to any of the others.

Two cells each contain the same 10 shapes. A hexagon is labeled target molecule. A blue T and Y are labeled detector molecules. In the left cell, the top of the Ts bind to the flat surfaces of squares, triangles, and hexagons, but not ovals or blobs. In the right cell, the mouth of the Ys only bind to the matching angles of two sides of the hexagons. — Specific detector molecules only bind to target molecules in the cell on the right