Description
The phosphate-buffered saline (often abbreviated as PBS, from the English phosphate buffered saline) is a commonly used buffering solution in biochemistry. It is a physiological solution containing sodium chloride, disodium phosphate, monopotassium phosphate, and a small amount of potassium chloride. Generally, the concentration of these salts is equivalent to that of the human body (isotonicity).
This buffer is primarily used for rinsing cells to remove any traces of medium before treating them. It is intended for use on cells maintained outside the CO2 incubator and is not designed for long-term incubations.
Its buffering capacity relies on the dihydrogen phosphate / hydrogen phosphate pair (pKa = 7.2), which is also one of the three major mechanisms for maintaining blood pH (HPO42– + H+ = H2PO4–).
The composition of 1X PBS is:
8.0 g/L of NaCl,
0.2 g/L of KCl,
1.42 g/L of Na2HPO4,
0.24 g/L of KH2PO4 for 1000 ml of distilled water.
Storage: RT, Attention, it crystallizes at low temperatures.
