hi,
what is the significance of 260/230nm spectroscopic reading of DNA

hi
i summarize what is on this web page from Hillary Luebbehusen
http://www.bcm.edu/mcfweb/Modified%20260_230%20for%20pdf.pdf

signifiance of 260/230 ratio is a measure to evaluate the purity of your prep regarding the organic compounds in solution (phenol, trizol and others aromatics like these).
The autir recommend strongly to use preps with a ratio 260/230 greater than 1.8

Fred_33

I have been experiencing problems (actually not a problem, just a nuissance) with a DNA extraction technique. It seems to be producing appropriate amounts of DNA, A260/A280 ratio looks fine but the A260/A230 Ratio is high (sometimes 5 sometimes even 20)... Besides the obvious "extremely pure DNA" option, does anyone have any idea what might be causing this? Has anyone experienced anything similar to this.. It happens with different resuspension buffers (TE10:1 and Tris 10 mM). Best.

I think some salts also absorb around 230 nm...I know Guanidinium Isothiocyanate does. Best. By the way, what is the significance of A260/A230 Ratios beyond 2 (higher than 2)?