I have isolated human genomic DNA from blood samples with a Promega DNA isolation kit. The DNA concentration is 65 ng/microlitter. If I want to obtain an intense band on agarose gel electrophoresis, what amount of genomic DNA should be loaded on each well?
"A band is clearly visible if it contains about 20ng"
https://www.methodbook.net/dna/agarogel.html
I literally just googled "DNA electrophoresis ng".
So probably just load a microliter, if you really want to do this.
A better question would be why you want to run genomic DNA on a gel?
Genomic DNA is massive, and even on a very low agarose % gel, most of it will barely leave the well.
You'll either have to fragment the DNA or use pulsed-field electrophoresis to get anything of particular value.
Most folks don't check concentration on an agarose gel for gDNA. Do you have access to a spectrophotometer or Qbit or nano drop?
It depends on the width and thickness of the wells and the intercalating dye used in the gel but using EtBr 10-20ng is plenty if it is good quality but if it is heavily degraded then it will be spread over a long distance and less visible
The amount of genomic DNA needed to obtain an intense band on agarose gel electrophoresis can vary depending on several factors, including the size of the DNA fragment, the percentage of agarose gel, and the concentration of ethidium bromide or other DNA staining dyes used. However, as a general guideline, loading 100-500 ng of genomic DNA per well can produce a visible and intense band on a standard 1% agarose gel stained with ethidium bromide.
Assuming you are loading DNA onto a standard 1% agarose gel stained with ethidium bromide, and that you want a very intense band, you could load 5-8 microliters of your genomic DNA sample (corresponding to 325-520 ng of genomic DNA) per well. However, you may need to optimize the amount of DNA loaded based on your specific experimental conditions. It is also important to include a DNA ladder or molecular weight marker on the gel to accurately estimate the size of your genomic DNA fragments.
These video playlists might be helpful to you:
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