FACS buffer (PBS + 0.5% BSA + 2 mM EDTA) recipe
The staining and wash buffer for flow cytometry: BSA reduces non-specific binding and EDTA prevents clumping.
🧮 Volume calculator
| Component | Amount | Final concentration (1X) |
|---|---|---|
| BSA | 2.5 g | 0.5% |
| 0.5 M EDTA (pH 8.0) | 2 mL | 2 mM |
| 1X PBS (Ca²⁺/Mg²⁺-free) | to final volume |
Steps
- Dissolve BSA slowly in PBS and add EDTA.
- Filter-sterilise through 0.22 µm. Store at 4 °C.
- Use ice-cold.
Good to know
- Some labs use 2% FBS instead of BSA.
- Add 0.05% sodium azide to reduce antibody internalisation when cells will not be cultured afterwards.
FAQ
Can I use it for sorting cells I will culture?
Yes — leave out azide and use sterile-filtered buffer.
This is a widely used standard composition. Amounts depend on the hydrate form and purity of your reagents — check the formula weight (FW) on the bottle and follow your institution's safety rules and the manufacturers' instructions.