A system for locating a cell for analysis. A capture structure is provided with a flow channel in the capture structure and a capture well in the flow channel. A fluid flows along the fluid flow channel and through the capture well. The cell flows with the fluid along the flow channel into the capture well but no further. In one embodiment a capture structure is provided and a flow channel and capture well are located in the capture structure. A fluid carrying the cell flows along the fluid flow channel and into the capture well. The cell flows into the capture well but no further.
 The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.