Fluorescent CF® dye tyramides are used for tyramide signal amplification (TSA) for increasing immunofluorescence sensitivity in multicolour immunocytochemistry (ICC), immunohistochemistry (IHC), or in situ hybridization (ISH).

• High-density labeling of a target protein or nucleic acid for enhanced immunoflorence sensitivity
• Especially suited for the detection of low abundance target
• Detection sensitivity of over 100-fold compared to conventional procedures
• Enables multiplex multicolor detection, not limited by antibodies from the same host species
• Bright, photostable and water-soluble CF® dyes are excellent options for fluorescent labeling

TSA is a highly sensitive method for differential gene or protein analysis or detection of low-abundance targets, in fluorescent ICC, IHC, and FISH applications. An antibody- or streptavidin-HRP conjugate catalyzes the deposition of fluorescent dye/biotin tyramides on tyrosine residues on and adjacent to a target protein or nucleic acid sequence in situ This results in high-density labeling of the target and significantly improves the detection sensitivity up to 100-fold compared to conventional methods. TSA is particularly advantageous for fluorescence detection in human tissue, where conventional ICC or FISH often fails to provide adequate signal over autofluorescence background. In applications where increased sensitivity is not required, TSA enables the use of significantly lower antibody or probe concentrations for the same level of detection sensitivity thereby reducing issues of non-specific binding or cross-reactivity. Furthermore, since binding of the tyramide label is covalent, a large number of targets can be detected in the same sample using multiple rounds of sequential TSA, in which the availability of antibodies from different host species is not a limitation. TSA also can be easily integrated with conventional immunostaining.

These conjugates are available with Biotium's next-generation CF® dyes, a series of highly water-soluble fluorescent dyes spanning the visible and near-infrared spectrum for labeling biomolecules such as proteins and nucleic acids. Developed in house by Biotium's industry-leading chemists, CF® dyes offer superior brightness, photostability, and signal-to-noise when compared to other commercially available fluorescent dyes.