Versatile Methods to Dispense Sub-Milligram Quantities of Solids using Chemical Coated Beads for High-Throughput Experimentation

High-throughput experimentation is a technique for screening multiple reaction conditions in parallel at micro or nanoscale without depleting precious starting materials. However, assembling a comprehensive screening set often involves the distribution of large number of solid reagents with diverse physical properties in small quantities. Automated solid dispensing, especially at submilligram scale, has long been a challenge with no practical and reliable solutions. This paper describes the use of our newly developed chemical-coated beads technology to provide a universal approach to the solid handling problem. This technology, when combined with an automated solid dispensing platform or calibrated scoops, can dispense submilligram quantities of a variety of solids with efficiency and adequate accuracy.