Fashioning Designer Drugs In Record Time

A researcher at Rensselaer Polytechnic Institute in Troy, N.Y., has found a building-block shortcut to designer drugs. Curtis M. Breneman, an RPI assistant professor of chemistry, can predict--in a fraction of the time it now takes--how the large molecules in a drug will interact with those in the body. The trick is to estimate the density and shape of the "electron cloud" that surrounds atoms and molecules. This cloud is what determines whether molecules will bind to each other and how.

Cloud density can be calculated precisely with esoteric quantum mechanical equations. But this takes months, even years, of computer time. Instead, Breneman and his team have created a library of simulated atoms from which big molecules can be constructed atom by atom.

Since the shape of an atom's electron cloud depends on adjacent atoms within the molecule, Breneman's technique accommodates these fluctuations. The result simulates a molecule's actual electron density to within 1% or 2%. That's good enough for most purposes, says Breneman. Indeed, a major drug company is already using his method to search for promising compounds.