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The therapeutic is taken orally, and makes its way to the stomach where it continues its journey through the digestive system.
When the therapeutic arrives in the stomach, the stomach bile will dissolve the outer shell of the therapeutic, exposing the E.Coli, and it will continue to the intestines.
By the time the therapeutic arrives in the small intestines, it will be ready to bind the microplastics to it, effectively cleaning the intestines of microplastics.
At this stage, the therapeutic will have microplastics bound to the E.Coli in it, so when the therapeutic is excreted, the microplastics will be excreted with it. This effectively rids your gut of the microplastics.