Increasing DNA Encoded Library Screening Resolution Using HT-SPR

DNA encoded library (DEL) technology has permitted substantial leaps in compound screening by enabling a more facile way to interrogate libraries and develop lead compounds. While a huge benefit to DEL technology is its reduction in the sheer number and tracking of discrete compounds through the screening process, it does come with a limitation in binding properties that can be gleaned for potential hits. In practice, from an initial screen numbering millions, the resulting thousands of hits are then reduced to around 50 compounds carried forward into downstream assays without any detailed characterization of their binding properties. These fundamental binding properties include kinetics as well as the target binding site. To address this resolution gap in DEL screening, demonstrated here is a technique to further characterize hits with improved resolution using high-throughput surface plasmon resonance (HT-SPR). HT-SPR characterizes the full kinetic profile for both weak and strong binders. Assay resolution can be further increased by inclusion of high-homology family members, truncated or mutated forms, binding partner disruption, etc., yielding a richer profile of lead candidates. With a screening capacity of thousands per week, HT-SPR affords a high-resolution technique that matches the throughput needs in this phase of discovery between the full library and a handful of leads. Additionally, this approach can work with any moiety having DNA attachment, including screening for targeted protein degraders (TPDs) and macrocycles.