Reliability Of DNA Quantification By Spectrophotometry

Quantify plasmid DNA by spectrophotometry

The concentration of nucleic acids in solution can be readily calculated from the absorbance at 260 nm. This figure shows the standard deviation of A260 measurements for serial dilutions of DNA. Although A260 values between 0.1 and 1.0 are very reproducible, A260 readings <0.1 and >1.0 lead to considerably lower reproducibility. Furthermore, readings above 3.0 are incorrect, which can potentially leading to underestimation of the DNA quantity. Therefore, for reliable spectrophotometric DNA quantification, A260 readings should lie between 0.1 and 1.0. When working with small amounts of DNA, quantification by agarose gel electrophoresis may be more reliable. electrophoresis may be more reliable.