UNIT 2.2 Quantitation of Nucleic Acids and Proteins

  1. Sean R. Gallagher

Published Online: 1 OCT 2008

DOI: 10.1002/9780470089941.et0202s00

Current Protocols Essential Laboratory Techniques

Current Protocols Essential Laboratory Techniques

How to Cite

Gallagher, S. R. 2008. Quantitation of Nucleic Acids and Proteins. Current Protocols Essential Laboratory Techniques. 00:2.2:2.2.1–2.2.29.

Author Information

  1. UVP, LLC, Upland, California

Publication History

  1. Published Online: 1 OCT 2008
  2. Published Print: JAN 2008

This is not the most recent version of the article. View current version (1 JUL 2011)


Reliable quantitation of nanogram and microgram amounts of DNA and RNA in solution is essential to researchers in molecular biology. In addition to the traditional absorbance measurements at 260 nm, two more sensitive fluorescence techniques using Hoechst 33258 and ethidium bromide are presented in this unit. These three procedures cover a range from 5 to 10 ng/ml DNA to 50 µg/ml DNA. Reliable quantitation of proteins is possible using several types of assays. UV spectroscopy is the simplest approach but is limited in sensitivity. More sensitive assays that use Coomassie blue binding, bicinchoninic acid (BCA), and the Lowry reaction are also described. All assays are prone to amino acid composition errors and interference from assay solution components. Flow charts and tables to help with appropriate method selection are included.


  • nucleic acid;
  • protein;
  • quantitation;
  • fluorescence;
  • colorimetric;
  • electrophoresis;
  • standards