A microwell device is provided. The device includes a plate having a upper surface. The upper surface has first and second recesses formed therein. Each recess has an outer periphery. First and second portions of microwells are formed in upper surface of the plate. The first portion of microwells are spaced about the outer periphery of the first recess and the second portion of microwells spaced about the outer periphery of the first recess. A first barrier is about a first portions of the microwells for fluidicly isolating the first portion of the microwells and a second barrier about a second portions of microwells for fluidicly isolating the second portion of the microwells.