Hi Pat,

I think that there´s not problem if you freeze your fragment DNA until you can follow the process.

Cool, thank you!

When water freezes the shard like ice crystals that form can shear DNA, if a substance such as glycerol, or DMSO is added to the solution (10-15% by volume) the water will freeze as a glassy solid without forming damaging shards. This should allow you to successfully freeze your DNA. If glycerol, or DMSO happen to be problematic in your assay, they are easily removed by dialysis.

Good luck.

Thanks a lot. I’ll try using DMSO.

It is generally recommended to perform DNA end repair as soon as possible after shearing in order to minimize the risk of damage to the DNA ends. This is because DNA ends are prone to degradation, and the longer the DNA is exposed to the environment, the greater the risk of damage.

However, it is possible to freeze sheared DNA for a short period of time before performing end repair, as long as the DNA is properly stored and handled. When freezing sheared DNA, it is important to use a suitable storage buffer that will protect the DNA from damage and to store the DNA at a low temperature, such as -80°C.

If you plan to freeze sheared DNA before performing end repair, it is recommended to store the DNA for no more than a couple of weeks, as longer storage times may increase the risk of DNA damage. It is also important to thaw the DNA gently and avoid exposing it to extreme temperature changes or other sources of stress during the thawing process.

Overall, it is generally best to perform DNA end repair as soon as possible after shearing, but it is possible to freeze sheared DNA for a short period of time before performing end repair as long as the DNA is properly stored and handled.

DMSO can be added to storage buffers or media to protect DNA from freezing damage during storage. It is generally recommended to use DMSO at a concentration of 5-10% in order to achieve optimal cryoprotection.

However, it is important to note that DMSO can also be toxic to cells and tissues, and it may interfere with certain downstream applications. For example, DMSO can interfere with PCR reactions and may produce false positives in some assays.

Thank you for your detailed response.