Abstract Scope |
In 4D printing, time is integrated as the fourth dimension with 3D printing. By preprogramming smart materials, 4D printing is able to manufacture structures that dynamically respond to external stimuli such as pH, light, temperature, water, magnetic field and chemicals. These kinds of materials are still in their infancy of development. Here, we report a natural protein from maize that can be prepared as gel in a simple, repeatable method, and the gel not only can be used directly as 3D printing ink, but also shows water-sensitive shape change with time due to its unique hydrophobic property. Tri-segment conduit and butterfly-shaped construct with two asymmetrical wings are printed to evaluate biomedical function either as a nerve conduit or as a drug delivery system. Adjustable drug loading, drug release rate and degradation rate can be achieved with this technique. Overall, this study extends the concept of 4D printing beyond shape transformation. |