Nucleic Acid concentration from OD260

Calculate the nucleic acid concentration of your DNA, RNA or oligonucleotides samples at the Optical Density 260 nm (OD260).

Different concentrations of DNA, RNA and oligos have different ability aborbing light. At OD260, the Absorbance of light and the nucleic acid concentration is calculated as follows:


C: the concentration of the nucleic acid, in µg/ml.
A: Absorbance at OD260.
l: width (in cm) of the cuvette used to hold the solution, usually is 1 cm.
e: Extinction coefficient of DNA, RNA or oligonucleotides. The extintion coefficient (at 1 OD260 unit) is the following:

50µg/ml for double stranded DNA (dsDNA)
40µg/ml for single stranded RNA (ssRNA)
33µg/ml for single stranded DNA (ssDNA)
20µg/ml for single stranded oligo (ssOligo)


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