Nanodrop question for RNA - (Jun/10/2014 )

bob1 on Thu Jul 10 21:02:13 2014 said:

 

Truz89 on Thu Jul 10 15:51:11 2014 said:

I have a similar, I have no experience with nanodrop, but I have extracted DNA using the QIAGEN kits and the 260/280 results range from 2.6-3.3. And the average DNA concentration is 122946 ug/ul 

I'm not sure what to make of those numbers, since they are higher than usual.

Check the DNA on a gel - results like that usually indicate contaminants of some sort.

 

The curve shown by the nanodrop should give you some idea if the samples are clean.

 

Incidentally, the nanodrop measures in ng/ul not ug/ul...

 

Just to make sure, the DNA extracted is from urine. Would that make a difference or does the 1.8 - 2 "rule" still apply?

thanks

 

It still applies - the ratio is dependent on the solvent of the DNA, not the source of the DNA.  Urine has lots of salts that might be relatively hard to remove, these could easily affect the extraction of the DNA and what you can do with it once you have extracted it.

bob1 on Fri Jul 11 00:54:06 2014 said:

It still applies - the ratio is dependent on the solvent of the DNA, not the source of the DNA.  Urine has lots of salts that might be relatively hard to remove, these could easily affect the extraction of the DNA and what you can do with it once you have extracted it.

ok thank you!

molbio1234 on Tue Jun 10 20:00:45 2014 said:

I have got a reading from RNA extracted sample with the following

A260/280  = 2.08

A260/230 = 2.26

A260 = 14.924

A230 = 7.191

 

Do these readings show good RNA?

 

 

The ratios look good, but it would be great to the whole curve. Phenol contamination will show up as a 270nm peak, which would add to absorbance at 260nm.