biotinylated oligos - (Jan/26/2006 )
i´m planning to do DNA affinity precipitation assays with biotinylated oligos. i have received the liophilized oligos but i don´t know how to resuspend them in order not to have biotin degraded or altered. water or some kind of buffer? should i freeze them after resunpension? maybe dmso or glycerol?
thanks a lot
IDTDna.com (the people who make our oligos answer this (when asked about Biotin labeled oligos):
The best way to store oligos is in the dry, lyopholized state at -20 degrees Celsius until the first day that you want to use them. When you want to use the oligos for the first time, it is best to elute them in a pH-controlled buffer and store the aliquotes at -20 degrees Celsius.
thanks for your answer! so then, should i resuspend them in PBS, for example? apart from that, the advise from roche (where we buy the oligos) written on the bag is that liophilized oligos shouldn´t be frozen. but i don´t know if this applies also for biotinylated ones. what do you think?
We use TE or water to resuspend our oligos. None of them are biotinylated though.
I routinely biotinylate oligos (usually about 30bp) and use them for emsa.
I store them at 4C in TE buffer for many months without degradation (assuming all is nuclease-free)
when I make them up, I usually take 1/2 of the reaction, or about 100 ul, and put it into two 50ul aliquots and store at -20 in case my others in the 4 C degrade. I have used the biotinylated oligos stored at 4C for over 8 months and seen no signs of degradation in my control samples.
thanks a lot aimikins!!!!!!
just for curiosity, why do you use biotinylated oligos for EMSA? don´t you use radioactivity?
I do not. we do not use anything that is radioactive in my lab.
and, the protocol is easy and works reliably, it is also fairly cheap