Researchers have created an unusual plastic that can self-destruct on a given signal. Spores of *Bacillus subtilis* were embedded in the material and “programmed” to produce two enzymes that work in tandem. The first enzyme cuts the long polymer chains into shorter fragments, and the second breaks them down into the original monomers—effectively completely “disassembling” the plastic into its components. The base material used was polycaprolactone—a common material for 3D printing and some medical devices. As long as the bacterial spores remain dormant, the plastic behaves normally: maintaining its strength and shape. However, as soon as the system is “awakened”—in the experiment, this was done using a nutrient medium at a temperature of about 50°C—the bacteria begin to degrade the structure. As a result, the material completely breaks down in just six days. The key advantage of this technology is that the degradation occurs without the formation of microplastics. The enzymes work sequentially and complete the process, rather than shattering the material into small but persistent particles. According to the authors, this approach could become a new tool in the fight against plastic pollution—especially if a convenient and safe activation mechanism can be implemented, for example, in an aqueous environment, where a significant portion of waste ultimately ends up. As a demonstration, scientists fabricated a flexible wearable electrode from this material: it correctly read electromyographic signals and then completely degraded in about two weeks.
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