An increased throughput method for determination of phase diagrams—method development and validation

The purpose is to facilitate preparation of large series of samples for phase diagram applications by using a robotic liquid handler together with a visual basic for applications, VBA, program. A method, i.e., a set of instructions and a VBA program have been developed and used together with a robotic liquid handler to prepare samples containing lipid (monoolein (MO)), solvent (1-methyl-2-pyrrolidinone (NMP), dimethylsulphoxide (DMSO) or acetonitrile (AN)) and water. The amounts of all components have been varied between 0 and 100% by weight. The sample-preparation concept has been validated by weighing dispensed amounts and also by the determination of and comparison to a previously known phase diagram. The accuracy of each component, when dispensing three components for a phase diagram study, is within ±1% of the total sample weight. In conclusion, the concept of using a robotic liquid handler for sample preparation of large series of medium-viscosity liquid components works excellently, as shown by the validation.