What is purpose of PBS buffer used for in the lab?

PBS is used to wash cells, dilute reagents, transport biological samples, and provide a stable environment for immunoassays and protein purification workflows.

Why is PBS considered isotonic and non-toxic to cells?

PBS contains balanced concentrations of sodium and phosphate ions, closely mimicking the salt concentration and pH of human physiological fluids, which helps preserve cell structure and function.

Can PBS interfere with antibody-based detection methods?

PBS is generally compatible with most immunoassays, but phosphate ions can interfere with certain metal-based labeling systems. For those cases, Tris-buffered saline (TBS) may be a better alternative.

PBS | Boston BioProducts

Phosphate Buffered Saline (PBS) is an isotonic, non-toxic buffer solution widely used in biological and biochemical research. With a physiological pH range of 7.0 to 7.4, PBS mimics the osmolality and ion concentrations of the human body, providing an ideal environment for maintaining cell viability, protein stability, and sample integrity.

PBS is commonly used for:

Protein purification and sample dilution

Blotting techniques and immunoassays (e.g., ELISA, western blot)

Cell washing and as a transport medium for biological specimens

Maintains physiological pH and ionic balance
Non-toxic and gentle on cells, even during extended incubations
Compatible with a wide range of lab protocols and detection systems

Whether you're working with cell-based assays, protein workflows, or diagnostic tests, PBS provides stable, reproducible conditions for your experimental needs.