These irrigating buffers and salt solutions are sterile, physiological balanced solutions intended for use in the maintenance of mammalian cells, where a chemically defined, balanced salt solution provides an environment that will maintain the structural and physiological integrity of cells in vitro. Applications include the intermediate steps for cultivation of cells, like washing, centrifugation, suspending and counting, as well as for many analytical methods or biochemical treatments. Principally these solutions should be used to keep the cells in suspension only for minutes or a few hours maximum. These buffers and solutions are not cell culture media.

They are comprised of a phosphate buffer system, sodium chloride to adjust the osmolarity and perhaps sugar for short term nutrition and stabilisation of morphology. For applications where Ca²⁺ and Mg²⁺ ions interfere with enzyme activity (eg. Trypsin) the modified buffers without calcium and magnesium should be used.