Regarding Presence of Mositure in Salts used for HPLC

[aniket]

Currentally i am working on HPLC, i am using different buffers, but i genrally use ammonium acetate as my buffer, many times i have observed if the container is not proprelly stored the salt abosrobs moisture, so i just wanted to ask is this moisture in any ways will affet my chromatogrphic performance?? i have thrown that bottle and using know one?? are their any speial precutions for storing ammonium acetate??

Please guide me on this

Aniket

[DR]

In the unlikely event that having an exact ammonium acetate concentration is critical to your separation, you should probably either dry an aliquot before weighing, do a moisture test before using and correct for the moisture present or use pH to determine how much to add. Chances are pretty good that, once you have "enough", you'll be fine unless you do run into a pH related issue (MP pH too close to pKa of an analyte).