RA. Lazarus and JL. Seymour (1986). Determination of 2-keto-L-gulonic and other ketoaldonic and aldonic acids produced by ketogenic bacterial fermentation. Analytical biochemistry, 157(2), 360-6. https://doi.org/10.1016/0003-2697(86)90638-x

PubMed 3777440

[Abstract]
The quantitative analysis of 2-keto-L-gulonic acid (2-KLG) produced by microbial fermentation is described. 2-KLG is separated from other aldonic and ketoaldonic acids by high-performance liquid chromatography on an Aminex anion exchange column with ammonium formate or potassium phosphate as the eluant. This is a rapid and simple method for routine analysis of a large number of samples generated by fermentation studies. Gas chromatography--mass spectrometry permits the qualitative and quantitative analysis of nanogram levels of 2-keto-L-gulonate in complex media and provides confirmation of the HPLC results. The methodologies presented are useful for the analysis of a number of aldonic and ketoaldonic acids.