• Compatible with both chemically and enzymatically synthesized siRNA
  • Label up to 12 siRNAs, one or both strands
  • Both Cy™3 and Fluorescein Labeling Kits available

Ordering Information

Sku Name Size Price Qty
AM1632 Silencer® siRNA Labeling Kit with Cy™3 dye 1 kit USD 676.00
AM1634 Silencer® siRNA Labeling Kit with FAM dye 1 kit USD 604.00
The Silencer® siRNA Labeling Kits are the perfect complement to the Silencer siRNA Construction Kit, but can also be used to label chemically synthesized siRNAs. Two labeling kits are available: Cy3 and FAM. Each kit comes with all the reagents necessary to label 65 µg of siRNA. Labeling reactions are scalable, but typically twelve 5 µg aliquots of siRNA are labeled per kit. Labeled siRNA can be used to analyze siRNA subcellular localization, stability, transfection efficiency, and to identify transfected cells for further analysis. Fluorescently labeled siRNA is particularly suited for use in double label experiments (with a labeled antibody) to track cells that receive siRNA during transfection and to correlate transfection with down-regulation of the target protein.

Figure 1 shows a silencing experiment performed with a Cy3 labeled GAPDH siRNA and a corresponding Cy3 labeled scrambled siRNA sequence prepared with the Silencer Cy3 siRNA Labeling Kit. The labeled siRNAs were transfected separately into HeLa S3 cells and then imaged by fluorescence microscopy. An anti-GAPDH antibody was used to monitor silencing of GAPDH expression. The siRNA to GAPDH has a strong silencing effect denoted by the lack of GAPDH protein expression (green) in Panel A compared to Panel B where the scrambled siRNA sequence was used. Each Silencer siRNA Labeling Kit comes complete with labeling reagents for 65 µg of siRNA, a GAPDH control for labeling, and a detailed Instruction Manual.



Figure 1. siRNA Silencing of GAPDH Gene Expression. siRNA to human GAPDH and a scrambled control were fluorescently labeled with Cy3 using Ambion's Silencer® siRNA Labeling Kit, transfected into HeLa S3 cells, and analyzed by fluorescence microscopy with an anti-GAPDH antibody. Red: Cy3 labeled siRNA; Blue: DAPI stained nuclei; Green: fluorescein labeled antibody to GAPDH. A. GAPDH is undectable in cells transfected with GAPDH siRNA. B. GAPDH is easily detected in cells transfected with scrambled control GAPDH siRNA.


Cy3 is a trademark of Amersham BioSciences.

The Silencer® siRNA Labeling Kits contain reagents manufactured  for Ambion by MIRUS.