1. Turn on OD absorbance spectrometer. Turn on UV source. Wait 5-10 minutes for the UV source
2. Rinse the quartz measurement cuvette with dH2O. Note plastic cuvettes are not
UV transparent, thus can't be used for UV measurement.
3. Adjust UV wavelength to 260 nm, fill the quartz cuvette with water. Zero the spectrometer, i.e., the OD reading for water should be 0.
4. Measure UV absorbance at 260 nm for the sample.
5. To correct for protein contaimnations, repeat steps 2-4 at the wavelength 280.
6. Calculate DNA/RNA concentration using the OD calculator of BioToolKit or use
the following estimations (for cuvette with 1-cm light path):
Double-stranded DNA concentration (mg/ml) = 50 * A260
Single-stranded DNA/RNA concentration (mg/ml) = 40 * A260
Oligonucleotides concentration (mg/ml) = 33 * A260
7. A260/A280 should be within 1.8-2.0. Otherwise the protein contamination is too high.
8. Clean up the cuvette, turn off the UV source and the spectrometer.