Phosphate-buffered saline or PBS buffer is a water-based salt solution widely used in cell culture applications, e.g. for maintenance of pH, dilution of substances, or rinsing of cell containers. Also known as Dulbecco's Phosphate-Buffered Saline (DPBS), PBS is non-toxic and provides cells with water and inorganic ions, which are necessary for cell metabolism. The osmolarity and ion concentrations of PBS solutions are meant to mimic the isotonic milieu of the human body. This formulation of PBS comes without Ca & Mg and without Phenol Red. The concentration of the solution is 1X.