FITC is a fluorochrome dye that absorbs ultraviolet or blue light causing molecules to become excited and emit a visible yellow-green light. This emission ceases upon removal of the light causing the excitation. FITC antibody is used to enhance the specific signal from a monoclonal antibody or a secondary antibody conjugated to FITC. The sensitivity of the FITC hapten-anti-hapten system makes it a useful alternative to other systems.
