To describe the preparation of 25X Phosphate Buffered Saline-0.05% Tween 20 (PBS-Tween 20) for use in ELISA assays.
- Per liter of 25X PBS-Tween 20 to be made, measure the following:
- 6.5 g Sodium Phosphate Monobasic, monohydrate
- 28.75 g Sodium Phosphate Dibasic, anhydrous
- 225 g Sodium Chloride
- 12.5 ml Tween 20
- 0.1 g Thimerosal
- Place the measured components into a container appropriate for the batch size.
Per liter of 25X PBS-Tween 20 to be made, add 950 ml deionized water to the container.
Add a stir bar, place container on stir plate and stir for approximately four hours at room temperature until all solids are dissolved.
Standardize pH meter at pH 4 and pH 7.
Measure pH of 25X PBS-Tween 20 while stirring. pH should be pH 6.0 - 6.2.
Place in closed container and label with contents, date and batch number.
Store at room temperature up to one year.