Copper staining: A five-minute protein stain for sodium dodecyl sulfate-polyacrylamide gels

doi:10.1016/0003-2697(87)90579-3

Analytical Biochemistry

Volume 166, Issue 2, 1 November 1987, Pages 308-312

https://doi.org/10.1016/0003-2697(87)90579-3 Get rights and content

Abstract

We present a new method for visualizing proteins electrophoresed in sodium dodecyl sulfate-polyacrylamide gels. After electrophoresis, gels are incubated in CuCl₂ to produce a negative image of colorless protein bands against a semiopaque background. Gels are stained completely within 5 min, do not require destaniing, and can be stored indefinitely without loss of the image. Because proteins are not permanently fixed within the gel, they can be quantitatively eluted after chelation of Cu with EDTA. The sensitivity of the CuCl₂ stain falls between that of Coomassie blue and silver. We anticipate that CuCl₂ will be useful in the rapid analysis of proteins by polyacrylamide gel electrophoresis and in the preparation of purified polypeptides by elution from gel slices.

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^☆: Research supported by NIH GM 31759.

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Copper staining: A five-minute protein stain for sodium dodecyl sulfate-polyacrylamide gels☆

Abstract

Anal. Biochem

Anal. Biochem

Anal. Biochem

Anal. Biochem

J. Biol. Chem

Anal. Biochem

J. Biol. Chem