Why does DNA have a wave length of A595nm and RNA a wave length of A660nm?
These are wavelengths to determine the concentrations of DNA and RNA. here’s teh reason why When you treat DNA or RNA according to your experimental protocol before you measure the absorbance, the phosphodiester bonds gets broken. Thus due to their sugar, basic composition the DNA and RNA will have different structures and different color absorbance values. So the color intensity is measured at 595 (or usually 600) to determine the concentration of DNA and in RNA it reads at 660nm. While if you are measuring the purity DNA absorbs UV light at 260 and 280 nm pure sample of DNA has the 260/280 ratio at 1.8 and is relatively free from protein contamination. A DNA preparation that is contaminated with protein will have a 260/280 ratio lower than 1.8.
