Staining Membrane-Bound Proteins with Ponceau S
This protocol was adapted from “Preparative 2D Gel Electrophoresis with Immobilized pH Gradients,” Chapter 4 in Proteins and Proteomics (ed. Simpson). Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, USA, 2003.INTRODUCTION
Because Ponceau S is relatively insensitive (~1 μg of protein), only the most abundant proteins will be visible. However, it is a reversible stain that can be removed completely with H2O prior to processing the blots. After staining, a soft lead pencil can be used to record the presence of visible proteins and molecular-weight markers, which will help when aligning the proteins detected on the membrane by western analysis with those in a total protein-stained gel or membrane. Ponceau S is compatible with both nitrocellulose and PVDF membranes.
