1X Phosphate Buffered Saline Tween-20 (PBST) Recipe

1. Dissolve the following in 800 ml of distilled H₂O
• 8g of NaCl
• 0.2g of KCl
• 1.44g of Na₂HPO₄
• 0.24g of KH₂PO₄
• 2ml of tween-20
2. Adjust pH to 7.2
3. Adjust volume to 1L with additional distilled H₂O
4. Sterilize by autoclaving

PBST is used in several protocols, most commonly as a wash solution in ELISA assays.