Bombyx mori (B. mori) silkworms have been used for thousands of years to generate silk fibers for the textile industry, based on the native process of spinning oval cocoons. Here we sought to modify the normal cocoon formation process by altering the spinning environment of the worms during the mounting (spinning) stage. The goal was to prevent traditional cocoon formation by removing steep gradients that are normally required to anchor and initiate the process, and manipulate fiber extrusion from and deposition by the worm in order to foster the biological spinning towards alternative material formats. Results were achieved based on direct observation of the worm’s innate behavior and environmental constraint required to spin a cocoon. Multiple artificial surface geometries and materials were used to establish platforms onto which the silkworms were placed and allowed to naturally spin silk into non-cocoon formats but yet new material architectures. Fiber alignment via the direct deposition of silk from a worm while moving over gaps or discontinuities in the surfaces was utilized to attain anisotropic spun fiber mats. Three dimensional silk mats were also constructed by placing the worms on pyramid structures with a gentle gradient. The methods employed demonstrate the versatility in utilizing natural spinning, in this case silkworm silk fibers, by modulating the environment in order to generate new material structures. This biologically-based biomanufacturing approach suggests new ways to think about materials fabrication, the formation of composite structures and the use of green methods for these goals.
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