Ethidium bromide

EB cannot pass through the living cell membrane, and the nuclear DNA can be dyed through the broken membrane of dead cells, which contains a flat group that can be embedded between stacked bases. The fixed position of the group is close to the base, which causes the dye to combine with DNA to produce fluorescence. Because the fluorescence yield of EB-DNA complex is far greater than that of the unbound dye, when the electrophoresis gel contains free EB, a small amount of DNA can be measured. It is a highly sensitive fluorescent reagent and an important fluorescent dye, and DNARNA is often measured Binding with DNA to inhibit DNA replication and transcription ethidium bromide is a highly sensitive fluorescent stain used to observe DNA in agarose and polyacrylamide gel. Ethidium bromide is excited and emits orange red signals with a standard 302 nm ultraviolet transmission meter, which can be photographed with Polaroid negative or gel imaging processing system with CCD imaging head. For gel staining after electrophoresis, the storage solution sample should be diluted to 0.5 with water first μ G/ml, and then incubate the gel for 15-30 minutes. It is not usually necessary to decolorize, but if it is necessary to reduce the background color, it can be decolorized in water for 15 minutes. Then the DNA bands can be detected in the ultraviolet light box (254nm wavelength). Ethylpyridine bromide can also be added to gel and electrophoresis buffer (final concentration 0.5 μ G/ml) and develop immediately after electrophoresis.