4 replies to this topic

[pcrmossad]

Hi All,

Can anyone tell me cDNA stability at 4C after diluting in Rnase free water.  I use Quanta bio sciences cDNA synthesis kit.

thanks in advance

[molgen]

The heteroduplex of the cDNA is a pretty stable molecule.
But I wouldn't keep it in the fridge for more than a week.
I usually store it at -20C for up to a year.

[pcrmossad]

molgen, on Mar 30 2009, 01:18 PM, said:

The heteroduplex of the cDNA is a pretty stable molecule.
But I wouldn't keep it in the fridge for more than a week.
I usually store it at -20C for up to a year.

hi,
suddenly my PCR come up at very late, that's why I ask. this has never happened before.  it worked until February but now it doesnt work. I have tried eveything.  so I think it may be cDNA, but can it degrade so fast??
how can i check??

[tea-test]

i don't know your cDNA kit but some are producing single stranded cDNA (or DNA-RNA duplexes) and I think they are not so stable compared to dsDNA.

[cheerioet]

tea-test, on Mar 31 2009, 01:34 AM, said:

i don't know your cDNA kit but some are producing single stranded cDNA (or DNA-RNA duplexes) and I think they are not so stable compared to dsDNA.

I am using kits like Monster Script 1st strand cDNA synthesis as well as Fermentas 1st Strand cDNA synthesis kit, both of them in the manual written the 1st strand cDNA product can be used directly for PCR or qPCR.

I am not so sure, if RNase H really necessary as the control positive shown up, but not my sample RNA to cDNA.