What equation can be used to determine the concentration of DNA?

The equation that is used to determine the concentration of DNA in a solution is based on the principles of spectrophotometry, where absorbance is measured at a specific wavelength. The correct equation incorporates the absorbance of the DNA sample, an absorptivity constant, and a dilution factor to calculate the final concentration effectively.

Absorbance is directly proportional to the concentration of the substance according to Beer-Lambert Law, which states that absorbance (A) is equal to the absorptivity constant (ε), the path length (l), and the concentration (c) of the solution:

[ A = ε \cdot l \cdot c ]

In this context, the absorptivity constant is essential because it relates how much light is absorbed at a given wavelength specific to DNA. The dilution factor accounts for any dilution performed on the original sample before measurement, ensuring that the calculated concentration accurately reflects the amount of DNA in the original sample before dilution.

Thus, the equation that includes the absorbance multiplied by the absorptivity constant and the dilution factor gives a precise calculation of the DNA concentration in the sample. This allows researchers to quantitatively assess the amount of DNA present, making it critical in molecular biology applications such as PCR, cloning