RESUMO
A novel method for revealing proteins after electrophoresis on cellulose acetate is described, based on adsorption of mixed gold-Tween 20 micelles onto TCA-fixed protein bands. The sensitivity is 2-300 times higher than conventional Coomassie Blue staining and ca. 10 fold higher than silver coloring, detecting barely 1 ng protein/mm2 gel. Acidic and ammoniacal silver dyeing, based on ionic silver, perform very poorly on cellulose matrices, while a new variant, colloidal silver, stains protein bands on a clear background, but with a sensitivity ca. 10 times lower than micellar gold. Urines, cerebrospinal fluid and other biological liquids can be revealed without resorting to a concentration step prior to electrophoresis. The method is simple to perform and does not require any destaining step.
