Chemiluminescent western blot detection is a highly sensitive alternative to isotopic detection of proteins bound to blotting membranes. Instead of radioactively labeled antibodies, enzyme-conjugated secondary antibodies produce a light signal while acting on the substrate. An enhancer intensifies the signal output, enabling the detection of picogram quantities of antigen. Also, it increases the duration of the light signal up to 6–8 hr. The light signal can be captured on film or an imaging system. The light signal continues 24 hr after initial activation, which allows flexibility in obtaining data. Exposure times on film are typically 30 sec to 5 min, depending on sample amount and antibody specificity. The Immun-Star™ AP chemiluminescence kit is therefore a highly sensitive, fast-acting alternative to isotopic detection.
These kits combine Bio-Rad's blotting reagents and expertise with CDP-Star chemiluminescence technology. Additional features of Immun-Star AP kits include:
- Working solution stability for 24 hr at room temperature
- Compatibility with both PVDF and nitrocellulose membranes
- Ability to reactivate a blot, even weeks later, with the addition of fresh chemiluminescent substrate
- Detection of as little as 10 pg of protein, comparable to the sensitivity of radioactive methods
- Possibility of stripping and reprobing
Two kits are available, based on goat anti-mouse or goat anti-rabbit conjugates.