Used extensively in cell culture and biological research, it provides a stable environment for maintaining cell viability and function. Commonly employed for washing cells during experiments to remove media, detach adherent cells, or dilute samples. It is also utilized in immunoassays, flow cytometry, and as a diluent for reagents. The inclusion of calcium and magnesium ions supports cell adhesion and membrane integrity, making it suitable for sensitive cell-based applications. Additionally, it serves as a buffer in various biochemical and molecular biology procedures, ensuring optimal pH and osmotic balance.