Preparation and evaluation of anion exchange open tubular column

An anion open tubular column (OTC) by coating cationic latex particle onto the silica capillary with surface sulfonate functionalized has been prepared and evaluated. The performance of the OTC was observed to be superior to that of those prepared by the bare silica capillary without sulfonation in term of separation efficiency. To increase the surface area of the capillary, acid and base-based etching method for treating silica capillary wall was carried out and compared. An OTC with multiple layers was prepared by alternatively coating cationic and anionic latex particles aiming to further increase the column capacity. The anion OTC with size of 50 μm i.d.×1 m long demonstrated good separation of common inorganic anions with high efficiency (e.g. for NO2−, its theory plate number is 11655 plate/m).