DPBS

Buffered Salt Solutions products:

Buffered salt solutions are made to a physiological pH and salt concentration. They are used alone or in combination with other agents for washing tissues and cells. Buffered salt solutions most commonly include sodium, potassium, calcium, magnesium, and chloride. They provide the cells with water and inorganic ions, while maintaining a physiological pH and osmotic pressure.
Although there have been many modifications to the original formulas in efforts to produce fully defined media, salt solutions still play an important role in tissue culture. A salt solution's basic function, to maintain the pH and osmotic balance in the medium and to provide the cells with water and essential inorganic ions, is as valuable today as when it was first developed a century ago.

DPBS, Dulbecco's Phosphate-Buffered Saline

A phosphate buffer, prepared from sodium phosphate, potassium phosphate and sodium chloride, where the pH is maintained by a phosphate--phosphoric acid equilibrium.
Dulbecco's Phosphate Buffered Saline (DPBS) is intended to provide a buffer system for maintaining cell culture media in the physiological range of 7.2-7.6. 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. 
DPBS may be used as a Calcium (Ca2+) and Magnesium (Mg2+)-Free solution for use in Trypsin solutions or it is available with Calcium and Magnesium salts where required. It generally serves as a general use isotonic saline solution or buffer for washing cells and tissues (e.g. in chromatographic procedures) where incubation is not necessary. DPBS without Calcium and Magnesium is used in the dissociation process to wash and resuspend cells when the presence of Calcium and Magnesium may inhibit Trypsin activity. 

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