APPENDIX 3J Detection and Quantitation of Radiolabeled Proteins and DNA in Gels and Blots
Published Online: 1 NOV 2002
Copyright © 2003 by John Wiley and Sons, Inc.
Lab Protocol Title
Current Protocols in Immunology
How to Cite
Voytas, D. and Ke, N. 2002. Detection and Quantitation of Radiolabeled Proteins and DNA in Gels and Blots. Current Protocols in Immunology. 50:3J:A.3J.1–A.3J.10.
- Published Online: 1 NOV 2002
- Published Print: AUG 2002
This appendix presents procedures for visualizing and quantitating radiolabeled proteins or DNA separated by polyacrylamide gel electrophoresis or affixed to filter membranes. Autoradiography is the most common method by which this is accomplished; X-ray film is the traditional recording medium. Film images can be analyzed by densitometry as described to obtain a quantitative measure of the radioactivity in the sample. The use of X-ray films for autoradiography, however, suffers from lack of sensitivity and limited linear range. Protocols are provided for overcoming these limitations using fluorography and intensifying screens, both of which enhance the radioactive signal. Sensitivity and linear ranges of measurement can be greatly extended by using a phosphor imaging system, which also makes it much faster and easier to quantify radioactive samples.