{"id":8922,"date":"2016-07-08T23:36:09","date_gmt":"2016-07-08T23:36:09","guid":{"rendered":"http:\/\/www.kurzweilai.net\/?p=284343"},"modified":"2016-07-10T23:36:26","modified_gmt":"2016-07-10T23:36:26","slug":"molecular-flip-in-crystals-driven-by-light-creates-microrobotic-propulsion","status":"publish","type":"post","link":"https:\/\/hoo.central12.com\/fugic\/2016\/07\/08\/molecular-flip-in-crystals-driven-by-light-creates-microrobotic-propulsion\/","title":{"rendered":"Molecular flip in crystals driven by light creates microrobotic propulsion"},"content":{"rendered":"
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(a) Sequential micrographs of one cycle of self-oscillation observed under 435-nm light and schematic illustrations. (b) Schematic illustration showing setup. (credit: Tomonori Ikegami et al.\/Angewandte Chemie)<\/p><\/div>\n

Hokkaido University researchers have designed a crystal material that continually flips between two positions like a paddle, propelling an attached structure, when stimulated by blue light. It could lead to bio-inspired\u00a0microrobots<\/a> that deliver drugs to target tissues, for example.<\/p>\n

The team made azobenzene-oleic acid crystals, composed of an organic compound called azobenzene, commonly used in dye manufacturing, and oleic acid, commonly found in cooking oil. Azobenzene molecules take two structurally different forms:\u00a0cis<\/em>\u00a0and\u00a0trans<\/em>, and they were found to switch back and forth when stimulated by the light.<\/p>\n

The frequency of the motion also increased with increased light intensity. Some crystal complexes they created even exhibited swimming-like motions in the water, the researchers report. Previously reported light-responsive materials have been limited in their ability to deform, the researchers noted.<\/p>\n

“The importance of this study lies in the realization of macroscopic self-oscillation by the repeated reversible reaction of a molecular machine with the cooperative transformation of a molecular assembly,” the researchers note in a paper published in the journal Angewandte Chemie<\/em>. “These results provide a fundamental strategy for constructing dynamic self-organizations in supramolecular systems to achieve bioinspired molecular systems.”<\/p>\n