7.5 M ammonium acetate recipe
A precipitation salt that also removes dNTPs and short oligos: add 0.5 volume (2–2.5 M final) plus 2–2.5 volumes of ethanol.
🧮 Volume calculator
| Component | Amount | Final concentration (1X) |
|---|---|---|
| Ammonium acetate | 28.91 g | 7.5 M |
| Water (distilled) | to final volume |
Steps
- Dissolve in water and bring to volume.
- Filter-sterilise (autoclaving drives off ammonia).
- Store at 4 °C.
Good to know
- Ammonium inhibits T4 polynucleotide kinase — do not use it before kinase reactions.
FAQ
Sodium or ammonium acetate?
Sodium acetate for routine work; ammonium acetate when you want to leave dNTPs and short primers behind.
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.