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Quantitation of DNA and RNA

Adapted from "General Procedures," Appendix 3, in Phage Display, by Carlos F. Barbas III, Dennis R. Burton, Jamie K. Scott, and Gregg J. Silverman. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, USA, 2001.

INTRODUCTION

There are several ways to quantitate solutions of nucleic acids. If the solution is pure, one can use a spectrophotometer to measure the amount of ultraviolet radiation absorbed by the bases. DNA can also be quantified by measuring the UV-induced emission of fluorescence from intercalated ethidium bromide. This method is useful if there is not enough DNA to quantify with a spectrophotometer, or if the DNA solution is contaminated. Strategies for accurately quantifying nucleic acids using these approaches are discussed here.