A digital dispense system for preparing samples for analysis, comprising: a fluid droplet ejection system housed in a housing unit, the fluid droplet ejection system including: a fluid droplet ejection head and fluid cartridge containing one or more fluids to be dispensed, a cartridge translation mechanism for moving the fluid droplet ejection head and fluid cartridge back and forth over a sample holder in an x direction; and a sample tray translation mechanism for moving a sample tray (14, 54) back and forth beneath the fluid droplet ejection head and fluid cartridge in a y direction orthogonal to the x direction; wherein the digital dispense system is characterized in that: the sample tray (14, 54) further comprises a glass slide adapter for holding one or more glass slides, and that; the sample tray (14, 54) further comprises a micro-well plate adapter for holding a micro-well plate, the sample tray (14, 54) further comprises a biasing means to bias the glass slides or micro-well plate in the sample tray (14, 54) to a predetermined location; the biasing means comprises a spring-loaded lever for positioning glass slides or a micro-well plate in the sample tray (14, 54) so that the glass slides or micro-well plate are in a predetermined location for fluid droplet ejection; and a distal end of the spring-loaded lever abuts a chamfer on one corner of the micro-well plate or a chamfer on one corner of a glass slide adapter. a fluid droplet ejection head and fluid cartridge containing one or more fluids to be dispensed, a cartridge translation mechanism for moving the fluid droplet ejection head and fluid cartridge back and forth over a sample holder in an x direction; and a sample tray translation mechanism for moving a sample tray (14, 54) back and forth beneath the fluid droplet ejection head and fluid cartridge in a y direction orthogonal to the x direction; wherein the digital dispense system is characterized in that: the sample tray (14, 54) further comprises a glass slide adapter for holding one or more glass slides, and that; the sample tray (14, 54) further comprises a micro-well plate adapter for holding a micro-well plate, the sample tray (14, 54) further comprises a biasing means to bias the glass slides or micro-well plate in the sample tray (14, 54) to a predetermined location; the biasing means comprises a spring-loaded lever for positioning glass slides or a micro-well plate in the sample tray (14, 54) so that the glass slides or micro-well plate are in a predetermined location for fluid droplet ejection; and a distal end of the spring-loaded lever abuts a chamfer on one corner of the micro-well plate or a chamfer on one corner of a glass slide adapter. the sample tray (14, 54) further comprises a glass slide adapter for holding one or more glass slides, and that; the sample tray (14, 54) further comprises a micro-well plate adapter for holding a micro-well plate, the sample tray (14, 54) further comprises a biasing means to bias the glass slides or micro-well plate in the sample tray (14, 54) to a predetermined location; the biasing means comprises a spring-loaded lever for positioning glass slides or a micro-well plate in the sample tray (14, 54) so that the glass slides or micro-well plate are in a predetermined location for fluid droplet ejection; and a distal end of the spring-loaded lever abuts a chamfer on one corner of the micro-well plate or a chamfer on one corner of a glass slide adapter.