Several detection systems are used in IHC: 1. Chromogenic Detection: Enzyme-linked secondary antibodies catalyze a color-producing reaction, commonly using substrates like DAB, which produces a brown color. 2. Fluorescent Detection: Fluorophore-conjugated antibodies emit light upon excitation, allowing for multi-color labeling and high sensitivity. 3. Polymer-Based Systems: These use polymer backbones to increase the number of enzyme or fluorophore molecules, enhancing signal intensity.
