The OD260=1.0 corresponds to how many micrograms per milliliter of double-stranded DNA?

The value of OD260=1.0 is significant in molecular biology as it is used to estimate the concentration of nucleic acids in a solution. For double-stranded DNA (dsDNA), an OD260 of 1.0 corresponds to a concentration of approximately 50 micrograms per milliliter (μg/ml). This relationship is derived from the fact that light absorbance at 260 nm (OD260) is directly proportional to the concentration of nucleic acids, and specific factors are established for different types of nucleic acids.

For dsDNA, the conversion factor is roughly 50 μg/ml per absorbance unit at 260 nm. Thus, when the optical density reaches 1.0, it indicates that there are approximately 50 μg/ml of double-stranded DNA in that sample. This measurement is crucial for applications that require precise quantification of DNA, such as PCR, cloning, or other molecular diagnostics techniques.

The significance of this conversion is crucial in laboratory settings for ensuring accurate measurements and subsequent analyses.