New silk-based material can include embedded, pre-designed functions
Mechanical components can now be designed with enhanced functionality, such as surgical pins that change color with strain.
Engineers at Tufts University have generated a 3D bulk material made from silk fibroin that can be programmed with unique functions. Using a water-based fabrication method based on protein self-assembly, the team is able to embed pre-designed biological, chemical or optical functions into the material.
The engineers were able to use the protein that gives silk it durability and manipulate the bulk material with water-soluble molecules to create multiple solid forms, from the nano- to the micro-scale, that have embedded, pre-designed functions.
The decision to use silk was based on the fact that its unique crystalline structure makes it one of the toughest materials. Fibroin, an insoluble protein found in silk, has a remarkable ability to protect other materials while being fully biocompatible and biodegradable.
Although the engineers note that more research is needed, the applications are endless. For example, the researchers created a surgical pin that changes color as it nears its mechanical limits and is about to fail, functional screws that can be heated on demand in response to infrared light, and a biocompatible component that enables the sustained release of bioactive agents, such as enzymes.
“The ability to embed functional elements in biopolymers, control their self-assembly, and modify their ultimate form creates significant opportunities for bio-inspired fabrication of high-performing multifunctional materials,” said senior and corresponding study author Fiorenzo G. Omenetto, Ph.D. Omenetto is the Frank C. Doble Professor in the Department of Biomedical Engineering at Tufts University’s School of Engineering and also has an appointment in the Department of Physics in the School of Arts and Sciences.
The team adds that applications could also include new mechanical components for orthopedics that can be embedded with growth factors or enzymes, a surgical screw that changes color as it reaches its torque limits, hardware such as nuts and bolts that sense and report on the environmental conditions of their surroundings, or household goods that can be remolded or reshaped.