Phosphate Buffered Saline segmentation by application reveals five dominant end‑uses that collectively drive market revenue. Cell culture accounts for the largest share, roughly 45 % of total sales, because PBS provides a physiologically balanced ionic environment essential for mammalian and microbial cell propagation in research and biomanufacturing. Molecular biology applications—such as DNA/RNA extraction, electrophoresis buffer preparation, and immunoassays—represent about 20 % of the market, reflecting the reagent’s role in maintaining nucleic acid integrity and enzyme activity. Clinical diagnostics consume close to 15 % of PBS, primarily as a diluent and wash solution in immuno‑histochemistry, flow cytometry, and point‑of‑care test kits, where sterility and isotonicity are regulatory requirements. Vaccine production contributes approximately 12 % as PBS is used for virus propagation, formulation, and stability testing, a segment that has expanded with recent pandemic responses. Finally, pharmaceutical formulation occupies the remaining 8 %, where PBS serves as an excipient in injectable drug development and as a reference buffer in stability studies. Together, these applications define the overall Phosphate Buffered Saline market size.