Sørensen formol titration

The Sørensen formol titration invented by S. P. L. Sørensen in 1907 is a titration of an amino acid with formaldehyde in the presence of potassium hydroxide.


 * RCH(NH2)COOH + HCHO + KOH &rarr; RCH(NHCH2OH)COOK + H2O

An unknown sample is reacted with a known amount of base. The remaining base is titrated with acid to determine the amount of excess base. The difference (total base less excess) is equal to the amount of amino acid present in the original sample.