US Patent 11988649 On-line suppressor

A device for ion chromatography comprises a tube with an inlet opening and an outlet opening and an inner diameter from about 40 microns to about 10 microns. There is an aperture through one side of the tube into a lumen of the tube. At least a portion of the inner surface of the tube has a first charge. An ion exchange barrier covers the aperture on an outside surface of the tube. The inner surface of the tube, from the inlet opening to the aperture, is coated with ion exchange particles having a diameter ranging from about 30 nm to about 200 nm. The ion exchange particles have a second charge opposite the first charge. The inner surface of the tube, from the outlet opening to the aperture, is not coated with ion exchange particles.