Congrats to Jen Kuang, Shanna Bonanno, and all the other co-authors on our new paper published in Matter! This project was a collaboration among students in our group, the Deravi Lab, and the Wilson Lab. Engineered Living Materials (ELM) integrate cells and materials with the goal of recapitulating the dynamics of living systems in nature, but with more controllable elements. Nevertheless, mimicking macroscale appearance changes of natural systems enacted by active cellular processes remains a challenge. In this work we developed an ELM composed of a pH-responsive hydrogel embedded with Escherichia coli. pH modulation driven by the central metabolism of the living component triggers reversible changes in the size and color of the hydrogel matrix. This work shows a proof-of-concept of an engineered living system that undergoes prescribed appearance changes based on a combination of materials and cellular engineering. It may potentially enhance the dynamic performance of other conventional materials and ELMs that have been used in drug delivery, hydrogel origami, and soft robotics applications. 

Here is a copy of the manuscript: Microbially-Driven Reversible Size and Color Changing Materials. It will also be on the Matter Journal website on April 11th, 2024 so you can check it out there too! The Joshi Lab is very proud to share this work!