DNA Makers FAQs
Q: Why are the DNA bands fuzzy?
A:
· Caused by low buffering capacity of the electrophoresis buffer. After the electrophoresis buffer has been used too many times, ionic strength decreases, pH increases, and buffering capacity decreases, which can cause fuzzy DNA bands or irregular DNA band migration.
· Excessive electrophoresis running time or too high voltage. Run the gels under voltage less than 20v/cm, and the temperature of electrophoresis should be lower than 30℃. If the voltage and temperature are too high, fuzzy bands or irregular DNA band migration may occur. In particular, too high voltage may cause missing bands. Electrophoresis produces heat, so too long running time may easily cause fuzzy bands, especially for small fragments.
· Old gel or poor quality of the agarose may result in reduced resolution of the DNA bands.
Q: DNA Marker degradation.
A: Nuclease contamination. It is recommended to use sterilized pipette tips and tighten the tube cap in time after use. Do not bring electrophoresis buffer into the tube when loading samples and changing with a new pipette tip is recommended.
Q: Why does the brightness of bands change over time for ethidium bromide staining agarose gel electrophoresis?
A: Because of different moving directions between DNA bands and EB during electrophoresis, the amount of combined EB changes over time, making the brightness of bands changes correspondingly. Therefore, it is recommended to use EB to stain the gel to achieve accurate quantification.
Q:Why do DNA markers separate poorly in electrophoresis?
A: The incorrect percentage of agarose gels causes low-resolution electrophoresis. Uneven gel also leads to abnormal electrophoresis. It is recommended to use a newly prepared gel and pay attention to the percentage error from operation when making a gel. Generally, for fragments with large molecular weight, low percentage gels are better for separation, while for fragments with small molecular weight, high percentage gel is better.
Q: Do the differences of nucleic acid dyes have influences on DNA Marker migration rate?
A: Pre-added GeneFinder, GelStain and GoldView in DNA markers have different influences on the migration rate of the markers.