Small molecules remain a viable drug lead despite the attention that biologics have garnered. There are many advantages to small molecules including cost of manufacturing and diversity of molecules that can be generated. Screening small molecules can be a challenge so researchers have resorted to screening pools or whole libraries of molecules and then trying to identify the binders. The advent of putting DNA bar codes on the small molecule now makes identification of positive hits an easy task. Also, researchers can take an iterative approach to screening libraries by subjecting the interaction assay to increasingly more stringent conditions. In this way the library is narrowed down to smaller and smaller pools of positive interactions and finally a set of high quality hits are identified.

Purifying drug libraries using PhyTip columns allows high throughput automation combined with high concentration and high quality (properly folded molecules).