Session: 05-09-02: Computational Modeling in Biomedical Applications - II

Paper Number: 95391

95391 - Study of the Influence of Different Geometries of an Organ-on-a-Chip 

Organ-on-a-chip (OoC)  platforms are the synergetic effect of combining microfluidics and cell culture. The first model was developed in 2010 and thenceforth, several OoC platforms have been adopted to obtain improved insights about the toxic effects of novel nanoformulations to combat countless pathologies. These devices have gained particular interest to speed up the development of groundbreaking drug formulations but also to make this process more efficient and less expensive. Numerous models have been developed so far, to recapitulate various organs, and the main differences between them lie in the culture model used (spheroids, organoids, or cells cultured two-dimensionally), the types of cells used, and the geometry. The latter is paramount to assure that the proper nutrient distribution is provided to cells, and this is directly related to the fluid flow behavior within the devices. Despite the importance of performing experimental studies, testing different geometries empirically is time-consuming and become expensive. In addition, the evaluation and understanding of several physical phenomena is difficult to perform. On the other hand, numerical simulations allow researchers to rapidly develop and test different OoC models and parameters and get an approximation of what happens in reality. This allows not only to better plan the experimental tests, reducing the costs and time spent, but also to obtain improved outcomes. Thus, these have been crucial in the development of preclinical platforms capable of accurately representing the human body on a microscale.

Aiming to evaluate the influence of geometry on fluid flow, in the present work, three different geometries of a single organ-on-a-chip were created and numerical simulations were conducted by using Ansys® Fluent software. Despite the geometric differences between the three models, all contain an organoid in the center region represented by a cylindrical body, which is the region of interest. The fluid flow of the culture medium with dissolved oxygen was simulated, whose properties were set according to the literature. Despite the benefits of using numerical software, there are some limitations and, therefore, it is necessary to develop user-defined functions to simulate in the best possible way the experimental conditions. For this reason, in this work, three user-defined functions were created to consider the consumption of oxygen by cells, the recirculation of the culture medium, the distinct diffusivities of oxygen in the culture medium and organoid, and assuming a laminar regime. In terms of oxygen consumption, the influence of the geometry was noticeable in the organoid region. In terms of velocity fields, the results were not significantly affected by the geometry.

Presenting Author: Violeta Carvalho University of Minho

Presenting Author Biography: Violeta Meneses Carvalho completed the Integrated Master in Biomedical Engineering in June of 2020 by the University of Minho and her area of expertise is Biomaterials, Rehabilitation, and Biomechanics. Currently, she is an invited assistant at the Production and Systems Department where teaches statistics and numerical methods. At the same time she is performing a PhD at the Mechanical Engineering Doctoral program at the University of Minho and also an internship at INL, International Iberian Nanotechnology Laboratory. Moreover, she is Guest Editor in the special Issue "Micro/nanofluidic and Lab-on-a-Chip Devices for Biomedical Applications“ (Micromachines, MDPI). Up to now she published 14 papers in ISI indexed journals, 3 book chapters, 1 edited book, 8 conference papers, 1 conference poster and 3 conference abstracts.

Authors:

Violeta Carvalho University of Minho
Nelson Rodrigues University of Minho
Raquel O. Rodrigues University of Minho
José C. Teixeira University of Minho
João Miranda Faculty of Engineering of the University of Porto
Rui A. Lima University of Minho
Senhorinha Teixeira University of Minho