Spontaneous manufacturing: alumina 128-well plates made by droplet drying

The radial flow inherent in the drying of a sessile drop has inspired the idea of preparing ceramic microwells from deposition of droplets of ceramic suspension. In this way, the shape of each well is created spontaneously without the need for a forming operation. A rectangular plate of alumina powder was made by conventional compaction and cylindrical discs were printed and sintered on its upper surface. A suspension containing the same alumina powder was printed on these discs to form droplets which were left to dry. As they did so, the powder spontaneously assembled at the periphery to form microwells. After sintering, a 128-well plate was prepared which is suitable for high temperature combinatorial experiments.