In lab, KAIST robots make drug scaffolds nonstop under visible light

A narrow tube, a thin stream of liquid and a beam of visible light: that is the heart of a new platform built at KAIST, the Korean Advanced Institute of Science and Technology, where a team led by Professor Yoonsu Park of the Department of Chemistry has built a chemistry lab that runs without researchers touching the equipment between steps. The robot mixes the raw materials, the pumps keep them moving, and the light starts the reaction. Afterwards, analytical equipment checks the result.

The problem the platform targets is familiar to anyone who works on drug development. Even when a computer proposes a molecule that might act as a medicine, it still has to be made before its efficacy and safety can be tested. Small changes in molecular structure can demand entirely new reaction conditions, and a process that succeeds at small scale can need adjusting again when production grows, because light or heat do not reach every part of the mixture in the same way. The team's answer is a continuous-flow process: raw materials are fed steadily through a narrow tube instead of being mixed in one large batch. The narrow tube helps light reach the whole solution evenly, and output rises by running the same process for longer.

The chemistry at the centre of the work is a single-atom editing method. It replaces the oxygen atom of furan, a starting material, with nitrogen, which turns furans directly into N-methyl pyrroles, a scaffold used in drug development. The team applied the method to more than 20 furan-based compounds, and reports that the desired part of even structurally complex natural products could be modified while the rest of the molecule stayed intact. Such modifications matter because they can change how a drug binds to proteins in the body.

For drug developers, the practical gain is speed in the comparison work. Testing usually means producing several slightly different versions of a compound and checking which binds better to a target protein or is less toxic. The platform is expected to make it easier to obtain those variants, and Park said the system should let reaction conditions be quantified and reproduced. The team gives no timeline for use beyond the laboratory, and it reports no yields, production volumes or costs, so the gain for pharmaceutical work remains a prospect that has yet to be measured outside KAIST.

For now, the result is a working laboratory platform, described in JACS Au, that shows a chain from raw materials to analysis can run without manual steps. If the reproducibility Park describes holds in other labs, the time between a designed molecule and a testable sample could shrink, but the paper does not yet say by how much.