Abstract: A holder (10) housing defines a plurality of individual wells (14) sized to retain a substrate such as a bio-chip (20) or microscope slide in a vertical orientation, and to retain a volume of liquid (22) sufficient to immerse the bio-chip. The wells are spaced-apart with an approximately 9 mm pitch and the holder has a form factor approximating an SBS Standard 96 well microplate. The holder configuration is such that it can be manipulated with standard robotic equipment (30), and can be fabricated using injection molding processes.