Article

Characterization of transport mechanisms for controlled release polymer membranes using focused ion beam scanning electron microscopy image-based modelling

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  • DigiM Solution LLC
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Abstract

Mass transport mechanisms of drug release inside a pellet formulation through polymer membrane were investigated with focused ion beam scanning electron microscopy (FIB-SEM). Through careful control of imaging conditions, sub-surface cross sectional images were acquired on two controlled release membrane samples. Image analysis of porosity, pore size distribution, and pore connectivity in 3D provided a matrix of parameters to quantitatively compare samples from different formulations and processing conditions. Image-based computational fluid dynamics simulations were employed to correlate membrane microporosity with flow permeability. Through high resolution FIB-SEM characterization, quantitative microporosity analysis, and mechanistic investigations of flow via image-based simulations, it was found that a 10% difference in the water content of the mixed aqueous-organic solvent used to dissolve polymers had a significant impact on the controlled release performance. This approach provides an analytical avenue to evaluate effects of permeation enhancers, solvents, and other process conditions on controlled release formulations.

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... The imagebased permeability simulations were conducted using DigiM I2S™. Pressure-driven fluid flow along three spatial directions were computed using a voxel-based computational fluid dynamics (CFD) solver (43). Finite volume spatial discretization was directly built on the porosity voxels of the segmented 3D image data of the tablets. ...
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... In this work, an artificial intelligence-based image segmentation algorithm (AIBIS) developed by DigiM was used to overcome the limitation of the conventional approach. The method has been discussed and validated extensively in a variety of pharmaceutical applications [27][28][29][30][31][32]. In brief, the AIBIS algorithm mimics the ability of the human eyes which can recognize a feature not only based on the greyscale value of pixels, but also its relationship with its surrounding pixels. ...
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Controlled release multiple units and single-unit doses
  • Bechgaard