Analysis of small-molecule interactions using Biacore S51 technology.

Biacore S51 is a new surface plasmon resonance-based biosensor developed by Biacore AB (Uppsala, Sweden). The instrument was engineered specifically to support small-molecule drug discovery and development. The platform includes increased sensitivity, larger sample handling capabilities, and automated data processing to improve throughput. Compared to previously released Biacore instruments, the most significant design change relates to the introduction of the hydrodynamic-addressing flow cell. This design allows two reaction surfaces and a reference surface to be placed within the same flow cell, thereby improving data quality and extending the kinetic range of the instrument. Using a set of small-molecule inhibitors of the enzyme carbonic anhydrase II, we tested the reproducibility, sensitivity, and dynamic range of the biosensor. Given the S51's performance capabilities, it should play an active role in secondary screening by providing high-resolution information for small-molecule/target interactions.