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Data, Data, Everywhere
By: Steve Herman
Posted: April 6, 2010, from the April 2010 issue of GCI Magazine.
page 2 of 4
“Combinatorial chemistry” is the fancy term for flinging multiple experiments against a wall and seeing what sticks. The history of combinatorial chemistry goes back to the work of Bruce Merrifield of Rockefeller University in the 1960s, which led to his Nobel Prize in Chemistry in 1984. Early work centered on peptide synthesis. By the 1990s, it became a primary method for drug discovery. The principles are now being applied to the complex interactions of some types of personal care formulations.
The perfume industry has used robots for years, both on a lab scale and in production. The nature of fragrances involves mixing hundreds of chemicals for each formula, and using a different formula for every customer and application, so a lot of repetitive work is involved. However, the robotics never became central to the fragrance creation process, just an extra pair of hands.
Major fragrance houses do use combinatorial chemistry to create new aroma molecules, making thousands of experiments to locate a handful of useful products. This is similar to the use of combinatorial chemistry in drug discovery. Lack of a precise structure-odor relationship limits the possibilities for the rational design of fragrance molecules, so trial and error can be the only feasible approach.
Applying the Tools
With robots making samples and the concepts of combinatorial chemistry and high-throughput screening, all that remains to be done is to apply the tools to complex cosmetic formulation issues. The Institute for Formulation Science is at the heart of just such an activity.
Robots exist that can make 2,000 formulas a day—a Beckman-Coulter Liquid Handler, for example, is capable of 350 an hour. They aren’t soup to nuts finished formulas but simple mixes that show critical interactions. The robot can make thousands of iterations, but surely a human must evaluate them. Not so—many observations, too, can be automated. A spectrophotometer can measure concentrations, and a crossed polarizer reveals liquid crystal structures. Adhesion (tackiness) can be measured with a flexible lens test.