Phosphate Buffered Saline (PBS) is a buffer solution widely used in biological research due to its isotonic and non-toxic nature. With a pH range of 7.0 to 7.4, PBS mimics the osmolarity and ion concentrations of the human body, making it ideal for applications including protein purification, western blotting and immunoassays, sample dilution, and as a transport medium. This buffer is also tested for endotoxins, minimizing the risk of contamination in later applications.