Perfect peak separation

A new technique looks set to surprise analytical chemists and revolutionise ion chromatography.

Brett Paull and colleagues in Dublin, Ireland, and Moscow, Russia, coated a chromatography column with a zwitterionic surfactant in order to employ their new technique dubbed ’double gradient’ ion chromatography. In doing so they changed its capacity, and its selectivity with varying pH. Operating simultaneous eluent flow and eluent pH gradients speeds up complex anion separation with remarkable efficiency.

Chromatographers are always looking to improve the resolution of their separations while reducing overall run times. The use of gradient flow rates with highly permeable monolithic stationary phases leads to fast separation, but without improving the overall selectivity. This limits the application of these columns to separations with big differences in retention volume.

The authors are excited by the potential their new technique has to change the way that liquid chromatography is performed. Their hope is to challenge conventional thinking about the scope of short monolithic columns.

Sula Armstrong