A System for Dispensing Sub-Milligram Doses of Active Pharmaceutical Powders for Early Stage Solubility Assays

At early stages of drug development, the solubility of compounds is an important screening criterion. However, because scientists lack the automated tools needed to perform comprehensive early stage solubility studies, they are only able to perform a small number of experiments by hand, thus exploring only a fraction of the potential formulation design space. To allow a larger formulation design space to be explored at relatively early stages of pharmaceutical development (when 100 mg of a prototype compound is available), TransForm has created the AquaSFinX™ and SFinX™ micro-solubility platforms. In this article, a novel solid deposition system is described which is an enabling component of TransForm's solubility platforms. Given 100 mg of a starting material, the deposition system can dispense over six hundred 50-μg plugs of powder into 384-well or 1,536-well plates with well openings as small as 1.5 mm. Currently no commercial powder deposition system can provide this functionality. Including the time required to characterize and run the system, the dispense times range from around 2 minutes per dose for small runs involving 100 mg of starting material, to 18 seconds per dose for larger runs involving a gram or more of starting material.