I could not find any suitable method to prepare acidic buffer solution by phosphate salts.
Hello! Because the first dissociation constant of Phosphoric acid, pKa1, is 2.16 (CRC Handbook of Chemistry and Physics, 90th edition; pages 8-40 and 8-41), you should be able to prepare an acidic phosphate buffer solution. Therefore, perhaps the following links might be of some assistance to you:
Sigma-Aldrich Buffer Calculator
http://www.sigmaaldrich.com/life-science/core-bioreagents/biological-buffers/learning-center/buffer-calculator.html
N. B.: This site will suggest which products you might need to properly make up your buffer solution at your desired pH.
Phosphate Buffer Calculator (clymer.altavista.org)
http://clymer.altervista.org/buffers/phos2.html
N. B.: This site uses Monsodium and Disodium phosphate percentages for Phosphate buffer preparation.
Excellent answer from CML. Make up a solution of phosphoric acid in deionized water the desired concentration - but keep to 0.8 final volume. Adjust to pH 3.0 with NaOH or KOH solution. Make up to final volume with more water; uncertain about concentration of alkali; high conc is needed to adjust pH of more concentrated buffer. rough and ready approach - does not allow control of ionic strength. Best W.
Dear All, EP buffer solutions manual is really helpful!. So many old friends "buffers" in one place. I like the fact that each pH value has many alternative buffers listed.
Something that follows on, is how to choose between buffers (if both give same pH values) for different application areas. For instance, avoid phosphate buffers if you are studying metal ion interactions. Nitrogen based buffers seem better for other applications. The choice of buffers for LCMS and other HPLC applications may interesting?
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