High-throughput particle capture and analysis

A system for capturing target entities that are, or are made to be, magnetic, the system comprising:

• a body comprising a chamber having an inlet and an outlet;
• and
• a micro-well array device arranged within the chamber between the inlet and the outlet, wherein the micro-well array device comprises:
• a substrate;
• a first array of micro-wells arranged on the substrate at or near the inlet, wherein micro-wells in the first array have a size that permits entry of only one target entity per micro-well and wherein each micro-well in the first array has approximately the same size;
• and
• a second array of micro-wells arranged on the substrate at or near the outlet, such that when a liquid is flowed across the substrate from the inlet to the outlet the liquid flows first across the first array and then across the second array, wherein micro-wells in the second array each have a size that is at least ten percent larger than the size of the micro-wells in the first array, and wherein each micro-well in the second array has approximately the same size.