A free online molecular biology calculator to help calculate the concentration of a nucleic acid solution (either DNA, RNA or oligonucleotides) from the optical density absorbance value measured by a spectrophotometer (using a wavelength of 260nm).
Instructions for DNA Quantification
- Follow the manufacturers guidelines for operating your specific spectrophotometer
- Dilute your sample as necessary in either water or TE buffer. TE buffer is best, to maintain a neutral pH
- Generally, blank the spectrophotometer using whatever buffer your sample is dissolved in.
- Measure optical density of DNA or RNA sample, enter absorbance value OD260 in the form below.
- Enter dilution factor. For example if you diluted 2µl of sample in 100µl of dH2O, the dilution factor would be 50.
- Enter volume of stock nucleic acid sample. for example if you had 1ml of DNA solution, enter 1000.
- Select strandedness of nucleic acid, are you measuring ssDNA, dsDNA or RNA?
- Click on Calculate!
- The results show total amount of nucleic acid in the sample along with the concentration per microlitre.