UNIT 10.6 Protein Detection in Gels Without Fixation

  1. Won-A Joo,
  2. David W. Speicher

Published Online: 1 MAY 2007

DOI: 10.1002/0471140864.ps1006s48

Current Protocols in Protein Science

Current Protocols in Protein Science

How to Cite

Joo, W.-A. and Speicher, D. W. 2007. Protein Detection in Gels Without Fixation. Current Protocols in Protein Science. 48:10.6:10.6.1–10.6.9.

Author Information

  1. The Wistar Institute, Philadelphia, Pennsylvania

Publication History

  1. Published Online: 1 MAY 2007
  2. Published Print: MAY 2007


A number of alternative methods are described for detecting proteins in polyacrylamide gels that do not require fixation of the protein either prior to staining or in conjunction with staining. The primary advantage of avoiding fixation is that this makes it easier to remove proteins of interest from the gels for subsequent analysis. In general, the sensitivity of protein detection methods that avoid fixation is lower than for detection methods using fixation. For any given method, sensitivity is dependent on the volume of the protein band within the gel; hence, sensitivity is highest for sharp, narrow bands. Techniques described in this unit include protocols for protein detection in gels by SDS precipitation, preparation of contact blots, staining with imidazole-zinc, and use of the fluorescent labels IAEDANS and fluorescamine. Several additional methods, including the use of tryptophan fluorescence, guide strips, and minimal protein staining, are discussed in the Commentary.


  • protein detection;
  • polyacrylamide gels;
  • protein stains;
  • SDS precipitation;
  • contact blots;
  • imidazole-zinc staining;
  • fluorescent labeling