Tween 20 can be found as a 10x and 20x concentrate and is considered a staining option to help you see abnormalities in the cells and tissues you research. However, many scientists wonder if it is necessary as a blocking buffer, especially if you’re trying to prevent the non-specific binding of your primary antibody in the next step. Most protocols suggest that you use Tween 20 in the blocking buffer stage, though you may, in the end, want non-specific binding of your blocking proteins during incubation.
Why It’s Needed
It’s important to understand that Tween 20 has a lower concentration in the blocking buffer stage, even if it is used for multiple antibodies or various stages. It is used to prevent interactions between non-specific proteins, and the specific binding may be more resistant or stronger than the detergent used.
However, weaker proteins, or those that are non-specifically bound proteins, can be washed away or prevented from binding, giving you a cleaner, more sterile environment. You will know for sure that your test was done correctly and that nothing else could have contaminated or changed your result.
Likewise, you can use it with BSA or Casein to imitate non-specific interactions between proteins, replacing all of the potentially non-specific-bound proteins that show a background or could be immunopositive with the other antibodies.
What It Is
Primarily, Tween 20 is a detergent that cleans the slides and keeps things sterile. It is usually mixed with Phosphate Buffered Saline as a wash buffer for IHC techniques, though it may be used with Western Blotting in some circumstances. It is in a concentrated form, whether 10x or 20x and should be diluted appropriately.
Tween 20 is an excellent way to clean slides and prepare them for use. Visit Spring Bioscience now to learn more.
