Compendial dissolution methods cannot simulate the dynamic environment in the gastrointestinal tract experienced by solid oral dosage forms in vivo. The biggest challenge lays in the simulation of mechanical and erosion stresses and pressures exerted on mechanically sensitive dosage forms as a result of stomach motility. The main goal of the research was the establishment of appropriate experimental conditions that simulate fasted stomach motility on a novel dissolution apparatus advanced gastric simulator - which can simulate the dynamic environment in the gastrointestinal tract in different ways. Fasted stomach motility can be described by a pattern of contractions called the migrating motor complex, comprised of four phases with characteristic contraction frequencies and amplitudes. Such parameters can be measured in vivo via different methods, including the pressure sensor of a Wireless motility capsule, SmartPill®. Experiments were started with the confirmation of a linear relationship between advanced gastric simulator settings and pressures generated in its lumen, measured with the SmartPill®. With the help of data on luminal pressures in vivo, we prepared a programme sequence, simulating the contractions during the four phases of the migrating motor complex. Pressures of up to 220 mbar were measured during the simulation and resembled the in vivo data. We finished the experiments with validation of the prepared programme sequence via dissolution testing of two hydrophilic matrix tablets with varying amounts of hypromellose. Drug release profiles were compared to the results of dissolution testing in the USP2 apparatus. When dissolution was performed in the advanced gastric simulator, larger differences between drug release profiles of both formulations were observed, compared to dissolution testing in USP2. Significant difference, compliant with in vivo behaviour of tested formulations, was acquired when dissolution media “Fasted State Simulated Gastric Fluid (FaSSGF)“ was used in the advanced gastric simulator.
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