Fluorescent Antibody. Microscopy of fluorescence requires a special type of light source, typically a lamp of mercury. The lamp light passes through special colored filters that only allow light to pass through with distinct wavelengths. When this narrow band of light hits the specimen, some compounds in the specimen (either natural compounds or fluorescent chemicals added) capture the light and reflect it as lighter.
First you must buy or prepare a fluorescein-labeled antibody. This antibody must be specific for the organism or protein you are trying to detect.
Prepare your sample by fixing it to the slide.
Add the fluorescein-labeled antibody. Give them time to bind,
Rinse off unbound antibody and observe the slide under a fluorescent microscope. If the sample contains the antigen of interest, it will emit light. The light from the lamp passes through special colored filters, which only allow light with distinct wavelengths to pass through. When this narrow band of light hits the specimen, some compounds in the specimen (either natural compounds or fluorescent chemicals added) capture the light and reflect it as lighter.
Is both sensitive and selective (needed mono-clonal antibodies) can be used on microbes that can not be easily grown can mark single cells can view cells in natural environment using different types of fluorescent-labeled antibodies, each with different dye, to see multiple types of cells in one sample.