Hello everybody,
Is it Ok to store it at -20 or better to store it in glycerol stocks at -80 ? and how to recover it again from glycerol to be used in cloning? and how many days or weeks can I keep it at 4 C°.
Thanks.....
Plasmids can be stored at -20°C for longer than a year as DNA is quite stable. If your plasmid will undergo numerous freeze-thaw cycles, it will degrade faster. Using a salt-stabilized buffer instead of water will help prevent DNA degradation. It is best to prepare enough plasmid DNA needed for all related experiments at once and keep multiple aliquots. Keeping DNA in glycerol may interfere with downstream applications like PCR and restriction digests.
Bacterial stocks should be made in glycerol (I aim for 50% final although there is a wide range) and kept at -80°C. When you need more plasmid, just take a small scrape of frozen cells and add to culture media with selective antibiotic.
DNA is still stable at 4°C although I cannot provide a half-life. If you are doing sensitive quantitative measurements, I would not recommend keeping DNA at 4°C, but rather take fresh aliquots from -20°C each time.
Plasmids can be stored at -20°C for longer than a year as DNA is quite stable. If your plasmid will undergo numerous freeze-thaw cycles, it will degrade faster. Using a salt-stabilized buffer instead of water will help prevent DNA degradation. It is best to prepare enough plasmid DNA needed for all related experiments at once and keep multiple aliquots. Keeping DNA in glycerol may interfere with downstream applications like PCR and restriction digests.
Bacterial stocks should be made in glycerol (I aim for 50% final although there is a wide range) and kept at -80°C. When you need more plasmid, just take a small scrape of frozen cells and add to culture media with selective antibiotic.
DNA is still stable at 4°C although I cannot provide a half-life. If you are doing sensitive quantitative measurements, I would not recommend keeping DNA at 4°C, but rather take fresh aliquots from -20°C each time.
I've never stored plasmids in glycerol, only bacterial stocks in 80% glycerol at -80C. I store stock plasmids in 10mM Tris, pH8 at -20C. And for long term experiments I've stored small plasmid aliquots at 4C for about a month and it has worked well.
Some of my plasmids were stored at -20C as water solutions for more than 20 years and they are still OK. As Philip suggested, aliquoting at -20 may help you to keep you plasmid safe.
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