What is the sensitivity of ethidium bromide?

40–100 ng bands
Sensitivity: 40–100 ng bands are reported to be detectable after de-staining. Toxicity: Non-mutagenic. Somewhat toxic if ingested.

Is EtBr light sensitive?

The photo to the left shows a bottle of EtBr. It is always kept in light-sensitive bottles because of its photosensitivity, and concentrated stocks should be handled with caution. If the gel shows bands after EtBr staining, a polaroid photograph is taken as a permanent record.

What is the detection limit for ethidium bromide?

0.5 to 5.0 ng/band
Ethidium bromide has UV absorbance maxima at 300 and 360 nm, and an emission maximum at 590 nm. The detection limit of DNA bound to ethidium bromide is 0.5 to 5.0 ng/band.

Why should you avoid contact with ethidium bromide?

Ethidium bromide is a powerful mutagen and is a skin, eye and respiratory irritant. It can be readily absorbed through the skin. Avoid direct skin contact!

What happens if you add too much ethidium bromide?

Adding too much ethidium on your gel can cause a lot of background fluorescence when visualising as well. Note that the SYBR Gold emission spectra is different from Ethidium Bromide as well so you might need a different filter on your imaging dock to see SYBR Gold-stained samples.

Why is SYBR green better than ethidium bromide?

SYBR® Safe Its major advantage is that it is as sensitive as ethidium bromide but does not require UV light for visualization. Toxicity: Documented as less mutagenic that ethidium bromide, but its acute toxicity is higher.

Does light degrade ethidium bromide?

Ethidium bromide is an intercalating agent commonly used as a fluorescent tag (nucleic acid stain) in molecular biology laboratories for techniques such as agarose gel electrophoresis. When exposed to ultraviolet light, it will fluoresce with an orange colour, intensifying almost 20-fold after binding to DNA.

Which one will be better substitute for EtBr and why?

GelRed™ is a commercial DNA stain manufactured by Biotium. It is marketed as being the most safe, sensitive and robust nucleic acid gel stain- less mutagenic than ethidium bromide, but more stable in storage than SYBR®Safe. Like ethidium bromide, GelRed™ is visualized using UV light.

What is the lowest limit of detection for DNA on an agarose EtBr gel?

How much DNA should be loaded per well of an agarose gel? The amount of DNA to load per well is variable. The least amount of DNA that can be detected with ethidum bromide is 10 ng. DNA amounts of up to 100 ng per well will result in a sharp, clean band on an ethidium bromide stained gel.

How do you test for ethidium bromide?

Some facilities use a handheld UV lamp to check for residual ethidium bromide contamination following spill cleanup. A reddish-orange fluorescence can be detected under both “long” and “short” UV wavelengths. Users of the handheld lamps should be aware that their ability to detect small spills is not guaranteed.

Why do you have to be very careful when working with EtBr?

EtBr is a potent mutagen (can cause genetic damage), and moderately toxic after an acute exposure. EtBr can be absorbed through skin, so it is important to avoid any direct contact with the chemical. The powder form is considered an irritant to the upper respiratory tract, eyes, and skin.

How much EtBr is toxic?

To put this further into context, EtBr is less toxic than salicylates (e.g., aspirin) and caffeine, which cause severe toxicity at serum concentrations of >750 mg/L [16] and >80 mg/L, [17,18] respectively.

How do you Destain EtBr?

Soak the gel for 15 minutes with gentle agitation. Longer staining times will result in high background. Rinse the gel with ddi water and destain with fresh ddi water for 15 minutes with gentle agitation.

How much EtBr do I put in gel?

approximately 0.2-0.5 μg/mL
(Optional) Add ethidium bromide (EtBr) to a final concentration of approximately 0.2-0.5 μg/mL (usually about 2-3 μl of lab stock solution per 100 mL gel). EtBr binds to the DNA and allows you to visualize the DNA under ultraviolet (UV) light. CAUTION: EtBr is a known mutagen.

How sensitive is SYBR Safe?

What is the lower limit of detection of SYBR Safe DNA Gel Stain? SYBR Safe DNA Gel Stain yields the same sensitivity as ethidium bromide—roughly 500 pg/band in a minigel, for fragments larger than 200 bp viewed on a 300 nm transilluminator.

How do you cancel EtBr?

Solutions containing ethidium bromide can be deactivated, neutralized and poured down the drain. Deactivation may be confirmed using UV light to detect fluorescence. Most ethidium bromide users are familiar with using household bleach as a method of deactivation.

What are the alternatives for EtBr?

However, there are safer alternatives to ethidium bromide. Products such as SYBR Green, Accuris SmartGlow™, and Apex Safe DNA Gel Stain are green fluorescent cyanine dyes that are highly sensitive and are non-carcinogenic, as determined by the Ames-test.

What is the minimum amount of DNA visible on gel?

10 ng
10 ng is the minimum amount of DNA to visualize it on agarose gel. The amount of DNA to load per well is variable. The least amount of DNA that can be detected with ethidum bromide is 10 ng. DNA amounts of up to 100 ng per well will result in a sharp, clean band on an ethidium bromide stained gel.

How does ethidium bromide make DNA visible?

Ethidium bromide is known as an intercalate agent as it inserts itself between the stacked bases of DNA. The ring structure of ethidium bromide resembles the rings of DNA bases and it is also hydrophobic. Ethidium bromide is fluorescent and is visible under UV light. This allows DNA to be visualized.

What is the working concentration of EtBr?

Ethidium Bromide (EtBr), a dark red, crystalline, non-volatile powder that is moderately soluble in water, is widely used in research laboratories as a visualizing agent for nucleic acids. The powder is used to make a stock solution of 10 mg/mL, and the working concentration for gel-staining is 1 µg/mL.

What are the limitations of ethidium bromide stain?

Ethidium Bromide Staining. Staining of denatured, ssDNA or RNA is relatively insensitive, requiring some 10 fold more nucleic acid for equivalent detection. Another limitation is that the fluorescence of ethidium is quenched by polyacrylamide, reducing sensitivity by 10-20 fold in PAGE gels.

What is the fluorescence of ethidium bromide?

The fluorescence of ethidium bromide in aqueous solution is significantly lower than that of the interchelated dye. Ethidium bromide is a sensitive, easy stain for DNA. It yields low background and a detection limit of 1-5 ng /band. The major drawback to ethidium bromide is that it is a potent mutagen.

What is the effect of ethidium bromide in gel electrophoresis?

The presence of ethidium bromide in a gel or added to samples just prior to loading the gel will retard the electrophoretic migration rate of nucleic acids by about 15%.

Can ethidium bromide be used to stain RNA?

Although ethidium bromide is routinely used to stain DNA in gels, ethidium bromide has also been used to detect protein–DNA complexes in band shift assays and to observe single DNA molecules during gel electrophoresis. Staining of ssDNA or RNA is less sensitive, often requiring 10 times more nucleic acid for equivalent detection.