How can I reduce background with SuperSignal West Atto Ultimate Sensitivity Substrate?
Here are potential causes for high background and corresponding solutions:
- Too much HRP in the system: Further dilute the HRP-conjugate, see guidelines in Table 1 in the user guide (https://assets.thermofisher.com/TFS-Assets/LSG/manuals/MAN0018858_SuperSignalWestAtto_UG.pdf).
- Inadequate blocking: Optimize blocking conditions.
- Inappropriate blocking reagent: Try a different blocking reagent. Use clear milk or StartingBlock blocking buffer instead of dry milk.
- Inadequate washing: Increase length, number or volume of washes.
- Film has been overexposed: Decrease exposure time or use Pierce Background Eliminator (Cat No. 21065).
- Concentration of antigen or antibody is too high: Decrease amount of antigen or antibody.
- Poor antibody specificity: Use SuperSignal Western Blot Enhancer (Cat. No. 46640).
We also recommend minimizing handling of the membrane, using clean gloves while handling, clean plasticware, glassware, forceps, or other contact surfaces. We also recommend trimming of the membrane to remove excess area.
Do I have to use a SuperSignal Western Blot substrate after using the SuperSignal Western Blot Enhancer?
Not necessarily. The SuperSignal Western Blot Enhancer will work with any chemiluminescent substrate (including SuperSignal Western Blot substrates), as well as colorimetric or fluorometric detection systems.
What is the difference between Western Blot Signal Enhancer and SuperSignal Western Blot Enhancer? Is there any benefit to one versus the other?
The reagents in both kits are different. Western Blot Signal Enhancer (Cat. No. 21050) is a 2-step pre-treatment that occurs before blocking. It basically relaxes the protein on the membrane making the epitope easier to detect. SuperSignal Western Blot Enhancer (Cat. Nos. 46640, 46641) contains a membrane treatment reagent and a primary antibody diluent that increase both signal intensity and sensitivity 3- to 10-fold compared to a detecion performed without it. We have found that SuperSignal Western Blot Enhancer shows much less background while enhancing signal and sensitivity when compared to Western Blot Signal Enhancer.
When should I use the SuperSignal Western Blot Enhancer (Cat. Nos. 46640 and 46641)?
The SuperSignal Western Blot Enhancer kit contains two reagents:
- Antigen Pretreatment Solution: used after transferring proteins to the membrane and before blocking or staining the membrane
- The Primary Antibody Diluent: used to dilute the primary antibody