Layered microfluidic array

A layered, microfluidic array, comprising:

• a first layer comprising a plurality of culture channels extending in a first longitudinal direction, each culture channel having a width and a plurality of traps, each trap comprising (1) a curved path and (2) a culture chamber, each culture chamber comprising a fluid diverter that diverts fluid into a bypass opening and a flow-through opening, the bypass opening uniting with the culture channel at a unification opening, the flow-through opening have a diameter between 10% and 50% of the width;
• a second layer comprising a plurality of microfluidic channels extending in a second longitudinal direction, wherein the first longitudinal direction and the second longitudinal direction are orthogonal;
• a third layer, disposed between the first layer and the second layer, the third layer comprising pores grouped into a plurality of nests, each nest horizontally arranged within the third layer such that each nest is vertically stacked above, and fluidly connected with, a corresponding culture chamber in the first layer, each nest fluidly isolated from adjacent nests by a fluid impermeable region of the third layer such that horizontal diffusion of water within the third layer is prevented;
• a fluid inlet connected to a first epd of the microfluidic channel;
• a fluid outlet connected to a second end of the microfluidic channel.