Engineered living materials (ELMs) are engineered materials made of living cells able to form or self-assemble material or modulate the functional performance of material. The foundations of ELMs come from synthetic biology and materials engineering. The design and development of ELMs brings together the fields of synthetic biology, materials engineering, nanotechnology, biomaterials, artificial intelligence and directed evolution. ELMs are not confined to biopolymers and biomaterials produced by nature.
ELMs involve bioinspired materials engineering. For example, a seed contains information for creating a tree, acquires energy from sunlight, uses the resources of carbons dioxide and water, uses cellular self-organization and molecular self-assembly. These characteristics are proposed to be replicated using synthetic biology to engineer cells to fabricate, assemble and maintain autonomously produced materials. The cells might be engineered to metabolize and use certain energy sources and materials. Synthetic morphogenesis would be used to program structures and complex organization.
ELMs is a research area within biohybrid materials. Biohybrid materials are classified as any composite material with both biologically-derived and synthetic components. Some examples of biohybrid materials include cells embedded in polymeric structures, microfluidic devices that recapitulate organ-level systems and wearables incorporating genetically engineered cells. In ELMSs living cells would act as materials factories similar to how biological systems self-replicate, synthesize biopolymers and modify its properties over its lifetime. ELMs are proposed to draw energy from their environment to generate biopolymeric building blocks and form or maintain the desired material. Materials such as biofilms could be secreted from cellular biomass as part of their structure. ELMs could be programmed to remove or kill living cells after forming the assembled materials.
A proposal for ELMs by Neel S. Joshi, Anna Duraj-Thatte and Avinash Manjula Basavanna, all at Harvard University, was one of the National Science Foundation (NSF) 7 winners of the first NSF 2026 Idea Machine prize competition.
The Defense Advanced Research Projects Agency (DARPA), an agency of the United States Department of Defense, has an ELM program aiming to apply research to military logistics and construction in remote, austere, high-risk, or post-disaster environments. One track of research aims to deliver hybrid materials composed of inert structural scaffolds that support growth of living cells for near-term uses outside of the laboratory. The second research track aims to discover fundamental engineering principles for the genetic programming of structural features in biological systems.
An example of ELM fabrication by 3D printing of bacterial endospores within a scaffold was published by Christopher A. Voigt's team at the Synthetic Biology Center at MIT. The tough structure of spores allow them to survive extreme environments and also be germinated in a spatially or temporally controlled manner. Since Staphylococcus aureus is a pathogenic bacteria that infects wounds, the researchers built a sensor that responds to S. aureus autoinducer peptide (AIP). The bacteria embedded in the ELM, Bacillus subtilis, were engineered to emit green fluorescence when exposed to S. aureus. Antibiotic-producing B. subtilis strains were shown to kill S. aureus on an agar plate in response to receiving induction signals. This type of spore-based ELM could be developed into a wound-healing patch that can be stored and germinated when needed, producing antibiotics and therapeutic molecules when pathogens are sensed.
A self-repairing brick made from living material was produced by Wil Srubar’s team at University of Colorado and supported by DARPA. Cyanobacteria were combined with scaffolding made of sand and gelatin. Cyanobacterial absorb carbon dioxide and exude calcium carbonate, which is a significant component of limestone sued in cement. When researchers split a brick in half and combined them with scaffolding, they regrew into two bricks.
