A bead dispensing system is provided for delivering small amounts of
substances onto substrates. The system can include, for example, a
movable support structure having an array of spaced-apart projections
depending from its lower side. An attraction source, such as a vacuum,
magnetic, and/or electrostatic force, is operable at each projection end
region to attract and retain one bead. The projection array can be
aligned with an array of bead-receiving regions of a substrate, e.g., an
array of spaced-apart wells of a micro-plate or card. In one embodiment,
a plurality of reagent-carrying beads are picked up, retained at
respective projection end regions, and moved to a location over a
multi-well plate. The beads are then released in a fashion permitting
each bead to land in a respective well. The system of the invention is
particularly useful for fabricating arrays of reagents.