Fluorescent stains typically use what type of marker for detection?

Fluorescent stains utilize antibodies attached to fluorochromes as the primary method for detection. This process relies on the specific interaction of the antibody with its target antigen, where the fluorochrome, a fluorescent dye, emits light upon excitation with a specific wavelength. This allows for the visualization of specific cellular components, proteins, or pathogens under a fluorescence microscope, often enhancing sensitivity and specificity in diagnostic applications.

In contrast to other options, chromogenic dyes are typically used in standard staining techniques that produce color changes rather than the fluorescent signal. Simple stains are used for basic visualization of cellular morphology and do not allow for the specificity provided by fluorescent techniques. Heavy metals are not used as markers for fluorescence; rather, they may be related to electron microscopy or other techniques that utilize different detection methods altogether. Thus, the use of antibodies conjugated to fluorochromes is critical for the distinctive capabilities of fluorescent staining in laboratory diagnostics.