Millifluidic chromatography plate

A chromatography plate comprising:

• a porous substrate (102);
• and
• at least one channel (104) on the substrate wherein the channel further comprises;
• a sample well (106) for the deposition of a solution;
• a ligand well (108) for the deposition of ligands;
• a mixing region (110) to allow mixing and interaction of the solution with the ligands;
• an elongated separating region (112) for the separation of the ligands and their complexes formed;
• and
• an effluent well (114) where excess solution from the channel collects;
• characterized in that the channel is millifluidic and the deposited ligands selectively form complexes with ions found in the solution and the mixture of ligands and their complexes then separate based on their interaction forces with the substrate along the separating region.