HILIC Separation of Carboxymethylcysteine and Betaine on Zodiac HST N Column

This HPLC method separates betaine and carboxymethylcysteine using a mixed-mode HILIC/ion-exchange mechanism. Both compounds are highly hydrophilic and exhibit poor retention on traditional reversed-phase columns. On the Zodiac HST N column, separation is achieved through a combination of hydrophilic interaction and ionic exchange. Operating in HILIC mode with Zodiac HST N allows for lower organic solvent concentrations, improving analyte solubility and enhancing method robustness. This approach is suitable for both qualitative and quantitative analysis of betaine and carboxymethylcysteine using ELSD or LC/MS detection.

In chemical terms, betaine refers to a class of neutral molecules possessing a positively charged onium group (e.g., ammonium or phosphonium) not bearing hydrogen, and a negatively charged group such as a carboxylate, which is not necessarily adjacent. Traditionally, the term was used exclusively for tetramethylglycine, but it now encompasses a broader class of zwitterionic compounds.