Characterization of an Inkjet Chemical Microdispenser for Combinatorial Library Synthesis

Solenoid inkjet valves are characterized and implemented in an automated chemical microdispenser, the ChemJet, to be used for combinatorial library synthesis. A novel high-density format for chemical synthesis and assay is also presented. The “ChemSheet” consists of a 48 × 48 array of 8-μL wells, molded as an 8 1/2-in. × 11-in. sheet of polypropylene. The development of the ChemSheet created the need for high-speed, parallel microdispensing. The ChemJet addresses this need by providing the ability to dispense 8-μL volumes of chemical reagents to the 2304 wells of the ChemSheet in under 10 s, with an average reproducibility of ∼2.2%. Results from both quantitative and qualitative characterization of inkjet solenoid valves are presented. Characterization of the ChemJet instrument is also presented.