Kits for reversible protein visualization and quantitation on protein gels and western blot membranes by labeling with near-infrared CF® dyes.

• Pre-label proteins or lysates with bright near-IR CF® dyes
• Linear: better western normalization than housekeeping proteins
• Reversible: allows the same channel to be used for western
• Sensitive: detect as little as 1 ng protein
• Accurate: detect 10% difference in protein content

VersaBlot™ total protein normalization kits are designed for rapid and sensitive protein detection on SDS-PAGE gels and western blot (WB) membranes. The proteins are covalently labeled with near-infrared CF® Dyes so that after electrophoresis, the bands can be immediately visualized by fluorescence detection without gel staining. The labeled proteins on SDS-PAGE gels can then be transferred to membranes for western normalization. The pre-stain can be reversed after scanning, allowing multi-color WB using antibodies conjugated to near-infrared CF® Dyes in the same channel.

For SDS-PAGE gel pre-staining, the kits allow detection of low concentration proteins down to 1 ng with minimal background. The dyes do not cause any visible change to the shape or mobility of the bands compared to unlabeled proteins visualized by post-staining methods. For western blot normalization, the kits demonstrate outstanding linearity for quantification of total protein contents over a wide dynamic range (0.1 to 15 μg), outperforming the traditional normalization method of housekeeping proteins detected by western. Compared to total protein post-staining products like the Ponceau S and LI-COR® REVERT™, VersaBlot™ uses a pre-staining protocol with superior signal-to-noise and sensitivity (able to detect 10% difference in protein content), with comparable reversibility and ease-of-use. The labeling and reversal procedures do not affect protein mobility or detection by antibodies (including phosphoprotein and glycoprotein detection).

CF®680T can be detected using the Typhoon™ (Cy®5 or IR Short filter) or on the Odyssey® in the 700 channel. CF®770T can be detected using the Typhoon™ IR Long filter or on the Odyssey® in the 800 channel.