200 mM sodium orthovanadate (activated) recipe
A tyrosine-phosphatase inhibitor that must be "activated" by boiling to work. Use at 1 mM final (1:200) in lysis buffers.
🧮 Volume calculator
| Component | Amount | Final concentration (1X) |
|---|---|---|
| Sodium orthovanadate (Na₃VO₄) | 368 mg | 200 mM |
| Water (distilled) | to final volume |
Steps
- Dissolve in about 90% of the final volume of water and adjust to pH 10.0 (it turns yellow with HCl).
- Boil until colourless (about 10 min) and cool to room temperature.
- Readjust to pH 10.0 and repeat boiling and cooling until the pH stays at 10.0 and the solution stays colourless (usually 3–5 cycles).
- Bring to volume, aliquot and store at −20 °C.
Good to know
- Activation depolymerises yellow decavanadate into colourless monomers — only the monomer inhibits phosphatases.
- For serine/threonine phosphatases add NaF (10–50 mM final) and β-glycerophosphate.
⚠ Safety Vanadate is toxic — wear gloves.
FAQ
It turned yellow again after thawing.
Polymers have re-formed — boil again until colourless or make fresh.
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.