A programmable living force sensor fabricated with surface engineered microbial network.

Engineered living materials have recently expanded into the field of bioelectronics when incorporating the rationally rewired microbes inside. Integrating living materials with force sensing provides an alternative route to overcome limitations of traditional sensors, such as fragility and stretching-sensitivity. Here, we present a programmable living force sensor fabricated by surface engineered microbial network with a bottom-up design for human-machine interfaces. Bacterial cells are genetically rewired to display surface-anchored affinity pairs that mediate the assembly of bacteria to macroscale. Functioning as the conductive and sensing layer, the microbial network is encapsulated in elastic tubes to fabricate the macroscopic force sensor. The resulting living sensor features a tunable measuring range, rapid self-recovery capacity within tens of milliseconds, and remarkably, excellent stretching-insensitivity with only ~30% increase in resistance under 800% of elongation. This bio-integrated approach enables microbes to prepare robust and reconfigurable force sensor suitable for tensile, dynamic and extreme mechanical conditions.