Adjust volume to 1 L with H 2 O. Sterilize by filtration. Store the solution in tightly sealed bottles at 4°C or at NACRES NA.21 General Reagents & Chemicals. Isn't it nonphysiological? You can buy crystal forms of ammonium acetate from Sigma. Ammonium acetate buffer pH=4 problems. Native ESI-MS involves the transfer of intact proteins and biomolecular complexes from solution into the gas phase. Prepare 800 mL of distilled water in a suitable container. Ammonium acetate nonetheless remains a useful additive for native ESI-MS. Used as a food acidity regulator, although no longer approved for this purpose in the EU. Ammonium acetate is sufficiently volatile for LC-MS use, but we are left with the 2.0