Hydroxystilbamidine bis(methanesulfonate)

Hydroxystilbamidine (also called Fluoro Gold) is a cationic dye used for staining DNA and RNA. It exhibits distinctively different fluorescence emission profiles when bound to DNA compared to RNA. It is also frequently used as a retrograde neuronal tracer. The fluorescent tracer provides intense retrograde labeling that is extremely sensitive and reliable, does not diffuse out of retrograde-labeled neurons, and can be pressure-injected or introduced by iontophoresis into cells. Hydroxystilbamidine is compatible with most frequently used neuroanatomical techniques such as immunofluorescence, immunocytochemistry, autoradiography, and horseradish peroxidase-based histochemistry, paraffin embedding. Gold color is emitted when tissue is processed with a neutral pH buffer while blue/bright white is emitted when an acidic pH buffer is used. Spectral data: λex=361nm and λem=536nm. In addition, hydroxystilbamidine is an amidine antibiotic with antibacterial antifungal, antitrypanosomal, antimalarial and carcinostatic activities. Binds to DNA and RNA in a non-intercalating manner, and is a powerful inhibitor of ribonucleases. Binds also to lysosomes.