Table of Contents
What causes dark bands in gel electrophoresis?
As the electrophoresis progress, positively charged ethidium bromide moves towards negative electrode, causing the depletion of ethidium bromide from the rear end of the agarose gel. This results in appearance of dark zone in the agarose gel when you analyze gel under uv trans-illuminator.
What do thick bands mean in SDS PAGE?
A dark, thick band indicates a highly abundant protein in the sample. A faint, thin band indicates that a relatively small amount of that protein is present in the sample. There may be a dye front at the bottom of the gel, which comes from the dye used in the sample buffer.
What do brighter bands mean in gel electrophoresis?
The gel matrix acts as a sieve: smaller DNA molecules migrate faster than larger ones, so DNA molecules of different sizes separate into distinct bands during electrophoresis. So, for example, 50ng of DNA in a band gives two times more (= brighter) staining than 25ng.
What do darker bands mean in SDS PAGE?
Darker band=more intensity=more protein conten. if your protein concentration in each lane is similar, the density of each band can be used as value for protein content comparison.
What causes band smearing?
Tip #1: Load less DNA Smearing and smiling in GelRed® or GelGreen® precast gels most often caused by overloading of DNA. If you see band migration shifts or smearing and smiling, try reducing the amount of DNA loaded. The recommended loading amount for ladders and samples of known concentration is 50-200 ng/lane.
What does a thicker darker band on electrophoresis results indicate?
A thicker, darker band does, as you might expect, mean that there is more DNA present, but this is not because you have more of that DNA in you! It takes a very small amount of your DNA as a starting point, and it amplifies it again and again. More amplifications means more DNA at the end of the process!
Why are some bands thicker than others in gel electrophoresis?
A thicker, darker band does, as you might expect, mean that there is more DNA present, but this is not because you have more of that DNA in you! The reason you sometimes have more DNA in one band and less in another is down to the technique we use to amplify your DNA in the first place.
What do bands on a gel represent?
For example, you collect DNA from a particular sample and extract it, set up your gel and run it. Depending on the DNA size fragment and length, different bands will appear across the length of the gel. My question are: Why is the DNA fragmented?
Why we sometimes see additional bands on the gel?
This finding suggests that formation of multiple bands in non-denaturing gel electrophoresis is a result of improper annealing of PCR fragments, rather than being the result of polymerase slippage and 3′ non-template extension, as has been reported previously.