An inverted microwell (102) provides rapid and efficient microanalysis system (100) and method for screening of biological particles (128), particularly functional analysis of cells on a single cell basis. The use of an inverted open microwell system (102) permits identification of particles, cells, and biomolecules that may be combined to produce a desired functional effect also functional screening of secreted antibody therapeutic activity as well as the potential to recover cells and fluid, and optionally expand cells, such as antibody secreting cells, within the same microwell.