Convert a blank-corrected A260 absorbance reading into an estimated nucleic-acid concentration. Select the conventional conversion factor, enter any dilution made before the reading, and view both the measured-aliquot and original-sample concentrations. A mass estimate for 100 µL is included as a convenient scale check, not as a purity or integrity assessment.
Original concentration (ng/µL) = A260 × Conversion factor × Dilution factor
Because 1 µg/mL equals 1 ng/µL, the conventional factors can be used directly in ng/µL.
The main result estimates the concentration in the original sample before any pre-read dilution.
UV absorbance is not sequence-specific and may include other absorbing substances. Review purity ratios and assay limitations separately.
For double-stranded DNA, A260 = 0.2 and a 10× pre-read dilution gives 0.2 × 50 × 10 = 100 ng/µL. The measured aliquot is 10 ng/µL.
It restores the measured aliquot concentration to the original sample concentration.
Use 50 µg/mL per A260 for the conventional double-stranded DNA estimate.
No. Concentration alone does not establish purity, integrity, or sequence specificity.
Both units describe the same mass-per-volume ratio after converting micrograms to nanograms and milliliters to microliters.
Yes. A blank-corrected zero produces an estimated concentration of zero.
| Material | Factor per A260 |
|---|---|
| Double-stranded DNA | 50 µg/mL |
| Single-stranded DNA | 33 µg/mL |
| Single-stranded RNA | 40 µg/mL |