Precautions 1. Smear cryo rack or sheet bands or carpet-like bands sometimes appear. Remove protein. The order of migration speed of these three different configuration molecules during electrophoresis is: cccDNA> IDNA> ocDNA. When TPE is used for DNA recovery, it will contaminate the phosphate with DNA and affect subsequent reactions. Shake slightly to get glue. All operations can only be performed in a dedicated electrophoresis area, wear disposable gloves, and change in time. Smear bands or smear bands appear in diluted DNA. Avoid nuclease contamination of DNA running out of the gel to shorten the electrophoresis time, reduce the voltage, and enhance the gel concentration of EB stained DNA.
Agarose gels are suitable for the separation of DNA fragments from 200bp to nearly 50kb, while polyacrylamide gels have the best resolution for small fragments (5bp-500bp) and have high resolution. The voltage should not exceed 6V / CM when electrophoresis is performed.
The amount of sample loaded can appropriately reduce the process of DNA degradation. The voltage during electrophoresis should not exceed 6V / CM. When the glue solution reaches about 60 ° C, add an appropriate amount of ethidium bromide solution to the glue solution. If high voltage electrophoresis is selected, polyacrylamide gels can be used. The amount of DNA loaded is not enough to increase the amount of DNA loaded. DNA denaturation.
The reason is often that the PCR system needs to be optimized and the PCR program needs to be explored. Under a certain electric field strength, the charge carried by the DNA molecule is ignored, and the migration speed of the DNA molecule depends on the molecular sieve effect, that is, the size and configuration of the molecule itself are the main influencing factors. Mix the sample to be tested with the loading buffer according to the appropriate ratio, and add it to the gel loading hole with a pipette. Check the buffering capacity of the electrophoresis buffer used.