Nucleic Acid - UV Vis Spectroscopy

Nucleic acid concentration determination is a common application in the life science industry. UV Vis spectroscopy is a popular method of this due to the accuracy of results and simplicity of use. For more information on the experimental method, please download the application note below.

How is Nucleic Acid Concentration and Purity Measured?  

Scans are performed at 260nm and 280nm since nucleic acid and protein absorb at those wavelengths, respectively. This isolates nucleic acid, and any remaining protein can be extracted with phenol in an additional step. After this, the purity of nucleic acid sample can be checked spectrophotometrically by calculating the quotient of absorbance at 260 and 280nm. If the ratio A₂₆₀/A₂₈₀ is between 1.8 and 2.0, the sample is 70-95% pure.

The experiment is carried out on the UV5Nano spectrophotometer which is accomodates both cuvette and micro-volume measurements. Only one micro-litre volume of sample is required for the latter, which is valuable for saving precious sample.