Getting Them to Stick

Derek Lowe tosses around some ideas for using small molecules as binding partners for immobilizing proteins to solid supports like beads and chips. Affinity chromatography is one way; surface plasmon resonance, which can tell with great sensitivity if something is sticking close to a solid surface, is another current approach that's making headway. "You want the association between the binding partners to be strong enough to be useful, but (in many cases) not so incredibly strong that it can never be broken up again," Lowe says. He adds: "The big problem that people tend to have with all these ideas -- and I’m one of those people, in the end -- is that it’s hard to see how you can rope small molecules to a solid support without changing their character."