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%recovery of 26mer-oligo-T purification by ethanol precipitation is very low - other oligonucleotides were about 80-95% (Aug/22/2006 )

Even 10 or 20 microgram of 26mer-oligo-T was used, but cannot see any pellet after: add 5M NaCl and cold absolute ethanol, 10 min at -20 degreeC, centrifuge at 13000 rpm 20 min. (others I can see). I tried isopropanol but the same. %recovery was about 1-2% maximum (by absorbance measurement at 260 nm). I used clean-up kit to purify, but because it's very short, %recovery cannot reach to 80-90%.
Please tell me about solving this problem.
Thank you very much.


hi nuut,

try 1/10 of 3M sodiumacetate + 2.5volumes of 100%ethanol,
20minutes -80°C, then 20min max RPM,
you should get a yield of >70%

good luck


butanol will gives you near 95% recovery.
Add 10volumes butanol, homogenize.
Spin 10000rpm 10', and if possible with low acceleration.
Then wash with etanol 70

No need of salts.
It's a tecnhique i use for reovering oligos after electroelution.
Works also well if sample is diluted in the 30ml : i had once a 30ng band.
I electroelute in 30ml...
i recovered 95% by butanol.

If 2 phases appear, discard the upper one and repeat the process as many as needed


Thank you very much.