The goal of this project was to develop, optimize and evaluate a prototype system that would enable the addition of libraries of drugs and biochemical molecules, reagents as well as cells from a 96 source plate directly into individual droplet compartments of the target Droplet Microarray (DMA). Thus, we evaluated a novel non-contact nanoliter liquid dispenser system, iDot printer, in combination with the DMA slides. The results of our studies demonstrate that iDot printer can deliver down to few nanoliters into precise locations on the DMA slides either dry or pre-filled with cell-containing 100 nL droplets. The printing volume precision, positioning precision, evaporation, cell printing, and compatibility with different solvents have been evaluated and optimized in order to realize the application of this liquid dispensing system for drug screenings and cell printings. We also evaluate the ability to print different cell types, single cells and to create cell patterns. Finally, the dispenser was utilized print cells capable for formation of cell spheroids via the hanging droplet method. Application of the iDot for printing of physiologically more relevant primary cells and cell screening was also positively evaluated. Last but not least, the obtained data were used to establish several important cooperations with industrial partners.
