Phosphate Buffered Saline (PBS) is intended to provide a buffer system for maintaining cell culture media. It generally serves as an isotonic saline solution or buffer for washing cells and tissues. It's utility in maintaining mammalian cells when a chemically-defined, balanced salt solution provides the appropriate milieu to sustain the physiological and structural integrity (i.e. tonicity/viability) of cells in vitro for a limited period of time. Biological Industries offers a range of PBS formulations.
PBS without calcium (Ca2+) and magnesium (Mg2+) is often used in trypsin solutions, and in the dissociation process to wash and resuspend cells when the presence of calcium and magnesium may inhibit trypsin activity.