Biotechnology and Bioinformatics (1+1)

Immunofluorescence

Immunofluorescence is an antigen-antibody reaction where the antibodies are tagged (labelled) with a fluorescent dye and the antigen-antibody complex is visualized using ultra-violet (fluorescent) microscope. Fluorochromes are dyes that absorb ultra-violet rays and emit visible light. This process is called fluorescence. Commonly used fluorochromes are Acridine Orange, Rhodamine, Lissamine and Calcofluor white. However, these fluorochromes are used for general fluorescence. When fluorescein (FITC) is excited by a blue (wavelength 488nm) light, it will emit a green (520nm) colour. Phycoerythrin (PE) emits an orange (570nm) colour. The fluorochromes commonly used in immunofluorescence are fluorescein isothiocyanate (green) and and tetramethyl rhodamine isothiocyanate (red)