Description_x000D_ General description_x000D_ PharmaGrade products are manufactured under appropriate controls for use as a raw material in pharma or biopharmaceutical production. For more information on the PharmaGrade Program, visit sigma-aldrich.com/safc-pharmagrade._x000D_ Application_x000D_ The pH values of all buffers are temperature and concentration dependent. For Tris buffers, pH increases about 0.03 unit per °C decrease in temperature, and decreases 0.03-0.05 unit per ten-fold dilution._x000D_ For precise applications, use a carefully calibrated pH meter with a glass/calomel combination electrode._x000D_ Tris HCl is a commonly used biological buffer. Tris/Tris HCl as a buffering system has a very broad usage in biological systems for biopharmaceutical manufacturing, cell culture, diagnostics and molecular biology. The pKa of Tris is 7.77 which corresponds closely to a physiological pH of 7.36._x000D_ Tris HCl is used as the conjugate buffer component with Tris/Tromethamine/Trizma in biopharmaceutical buffer formulations (both upstream and downstream applications), electrophoresis separations and diagnostic reagent formulations._x000D_ Packaging_x000D_ 100 g in poly bottle_x000D_ 5, 25, 50 kg in poly drum_x000D_ Linkage_x000D_ Enhanced Quality Product Documentation on PharmaGrade TRIS Hydrochloride_x000D_ Legal Information_x000D_ Trizma is a registered trademark of Sigma-Aldrich Co. LLC