Western blot

Conjugated Polymer Nanoparticles (CPNs™) can enhance western blot analyses, allowing highly sensitive detection of a protein of interest. When linked to key antibodies, the powerful brightness of CPNs™ identifies even low concentrations of the protein, improving the detection limit when compared with conventional methods.

In addition, CPNs™ can be used to quantify the protein of interest. The intensity of the fluorescent signal is linear to the amount of protein detected on the blot, allowing accurate quantification of protein over a wide range of concentrations.


Key advantages

  • Extremely bright signal, allowing detection of very low levels of protein
  • Fluorescence resistant to photobleaching, ensuring signal remains stable for reliable detection and archiving
  • Signal is directly proportional with a linear relationship to the protein concentration, allowing reliable protein quantification of a wide range of concentrations
  • Wide range of CPN™ colours allowing compatibility with a range of image capture systems and simple multiplexing
  • Quick and easy linkage to key antibodies via our new LINKBRIGHT™ conjugation kits


The protein samples, mouse-anti-CD44 (500ng and 1µg), were loaded onto a 10% SDS-PAGE and transferred to a PVDF membrane. After being blocked (5% milk and 0.05% TWEEN-20 in PBS saline (PBS-T)), membrane was incubated at room temperature 30 min with CPNTM  900 conjugated anti-mouse-IgG (ab6708, Abcam) (diluted in 5% mike in PBS-T). The western blot signal was visualised by ImageQuantTM 800 (with IR long filter).

Experimental data shows that CPNs™ can produce a strong and robust signal in western blot analysis, allowing clear identification of the protein or proteins of interest, visible even after storage for extended periods of time. As a result, CPNs™ prove useful tools for sample analysis and protein detection in a range of molecular biology applications.

Impressive signal sensitivity

CPNs™ have displayed levels of detection far more sensitive than conventionally used dyes, showing superior signal strength when linked to matching quantities of antibodies in western blots. This allows low levels of the protein of interest to be clearly identified and quantified.

Western blots produced by CPN™ 510B (green), CPN™ 900 (IR-I) and CyDye 800 at matching concentrations.

The powerful brightness of CPNs™ facilitates the detection of picogram levels of protein on a nitrocellulose membrane, as shown below in dot blots when compared with CyDye 800. This enhanced detection enables highly sensitive western blots.

CPN™610 (Orange) detection of low levels of anti-CD44 in dot blots. Imaged using ImageQuant800, compared with CyDye 800 detection. Imaged using ImageQuant 800.

Get these benefits in your western blot analyses quickly and simply with our new LINKBRIGHT™ antibody conjugation kits, or get in touch for more information.