Control system for simulated moving bed chromatography

The present invention provides devices and methods for micro-scale simulated moving bed chromatography (SMB) for continuous preparation of analytic quantities of highly pure fractions of target molecules. The present apparatus and method of the invention is adapted in a preferred embodiment to separations by affinity chromatography involving three discontinuous liquid flow loops. An alternative embodiment of affinity chromatography utilizes standard SMB operating under isocratic conditions.