Even after the detailed computer modeling that went into it, the outcome came as a bit of a surprise, Buehler says. One of the new materials produced very strong protein molecules but these did not stick together as a thread. The other produced weaker protein molecules that adhered well and formed a good thread. "This taught us that it's not sufficient to consider the properties of the protein molecules alone," he says. "Rather, [one must] think about how they can combine to form a well-connected network at a larger scale."
The team is now producing several more variants of the material to further improve and test its properties. But one wrinkle in their process may provide a significant advantage in figuring out which materials will be useful and which ones won't and perhaps even which might be more advantageous for specific uses. That new and highly unusual wrinkle is music.
The different levels of silk's structure, Buehler says, are analogous to the hierarchical elements that make up a musical composition including pitch, range, dynamics and tempo. The team enlisted the help of composer John McDonald, a professor of music at Tufts, and MIT postdoc David Spivak, a mathematician who specializes in a field called category theory. Together, using analytical tools derived from category theory to describe the protein structures, the team figured out how to translate the details of the artificial silk's structure into musical compositions.
The differences were quite distinct: The strong but useless material translated into music that was aggressive and harsh, Buehler says, while the one that formed usable fibers sounds much softer and more fluid.
Buehler hopes this can be taken a step further, using the musical compositions to predict how well new variations of the material might perf
|Contact: Sarah McDonnell|
Massachusetts Institute of Technology