New dynamic digestion model reactor that mimics gastrointestinal function

Abstract

A new dynamic model that mimics gastrointestinal function was designed. Elastic and contractile silica gel with gastrointestinal rugae and folds were used to simulate the stomach and large intestine, and silica gel with intestinal folds and villi was utilized to simulate small intestines. Mixing times for Newtonian fluids with Reynolds numbers of 10–5000 and for non-Newtonian fluids with Reynolds numbers of 1–100 were shortened in the new dynamic model bionic gastrointestinal reactor (BGR) compared with those in a traditional stirred tank reactor (STR). Gastric pressure of stomach at different digestion phases in the range 20–220 mm Hg was simulated by adopting different motion models. Maximum force of 0.72 N was observed when using agar beads to mimic solid foods. The folds and villi increased the surface area of the modeled small and large intestine walls by 112 % and 52 %, respectively. As a result, mixing and grinding in the simulated tract was improved. In the future, BGR can be applied for simulated studies on digestion and metabolism of foods and drugs in a mimetic gastrointestinal tract environment.