Power Your Assay With Styramide™ Signal Amplification Technology

news November 21 2019

Power Styramide™ Signal Amplification (PSA™) is an ultrasensitive detection method for high-resolution imaging of low-abundance targets in cells and tissues. By combining the superior brightness, photostability and water solubility of iFluor™ dyes, PSA™ imaging can generate fluorescence signals with significantly higher precision and sensitivity (more than 100-fold greater) than conventional immunohistochemistry, immunocytochemistry and immunofluorescence methods.

Similar to tyramide signal amplification (TSA), PSA™ labeling uses the catalytic activity of horseradish peroxidase (HRP) for the covalent deposition and binding of labeled-Styramide™ onto a target protein or nucleic acid sequence in situ. Since the added labeled-Styramide™ are deposited in close proximity of the HRP-target site, there is minimal diffusion-related loss of resolution. Moreover, PSA™ imaging technology can be readily added to any application that allows for the integration of HRP into its protocol, such applications include, IHC, ICC, IF, in situ hybridization and ELISA.
Available PSA™ Reagents & Kits:
Available Tyramide Reagents:
  • iFluor™ tyramide
  • Cy3-tyramide & Cy5-tyramide
  • Alexa Fluor® equivalent dye-labeled tyramide

PSA™ Imaging Technology

PSA™ imaging provides numerous benefits when added to any IHC, ICC, or IF application, including:
  • Increased detection sensitivity more than 100-fold greater than standard IHC, ICC, IF methods
  • Improved fluorescence signal 10 to 50-fold greater than tyramide (TSA) reagents
  • Higher reactivity of PSA™ radicals allow for a faster, efficient and more robust labeling of styramide conjugates at the HRP-target interaction site
  • Conserve precious antibodies, PSA™ labeling allows use of significantly less primary antibodies or probe without any sacrifice in detection sensitivity
  • PSA™ imaging kits are easy-to-use and provide sufficient reagents for 100 tests

Superior Detection Sensitivity

Figure 1. Sensitivity of Power Styramide™ Signal Amplification (PSA™) Kits. HeLa cells were fixed, permeabilized and labeled with various concentrations of rabbit anti-tubulin primary antibody. The manufacturer recommendation was 1:500 dilution or 2 µg/ml. Cells were then stained with reagents in our iFluor™ 488 PSA™ Imaging Kit with Goat Anti-Rabbit IgG, an Alexa Fluor® 488-labeled tyramide or an Alexa Fluor® 488-labeled goat anti-rabbit IgG. Cell images were captured from each treatment under the same conditions (using a FITC filter set and analyzed with the same exposure time). Relative fluorescence signal intensity was measured and compared between different detection methods.

PSA™ Workflow – compatible with standard IHC, ICC & IF procedures

PSA™ imaging technology can be used in any application that supports the addition of HRP into its protocol. In conventional IHC, ICC and IF applications, use of PSA™ results in a significant increase in detection sensitivity without any loss in image resolution or increase in background noise. Similar to the workflow of standard IHC, ICC and IF procedures, PSA™ imaging is easy-to-perform comprising of a few simple processes (Figure 2).

Figure 2. Workflow for Power Styramide™ Signal Amplification (PSA™). With workflow similar to conventional ICC and IHC methods, PSA™ kits and Styramide™ reagents can achieve sensitive detection of desired targets in a few simple steps.