MBA™ Fluid Circulation & Material Retention Properties
Spherical-shaped MBs have unique properties of fluid flow as compared to typical micro-physiologic system (MPS) devices. Typical MPS devices culture cells in direct contact with fluid flow which imparts shear stress. For certain cell types including endothelial cells, shear stress is physiologically important to recapitulate in vivo function. However, most cells and tissues in the body are not subjected to shear stress at the levels imparted in typical microfluidic MPS devices. Cells and tissues cultured in MBA™ mounted in a microfluidic system experience low shear stress but with well developed fluid flows within the MB important for reagent and nutrient delivery. Nidus explicitly leverages these properties to obtain superior performance in multiple application areas.
The figure is reproduced from a publication in collaboration with Dr. Michael King (Agastin et. al. “Continuously perfused microbubble array for 3D tumor spheroid model.” Biomicrofluidics. 2011 Jun; 5(2):24110) that shows fluid flow within and over a MB. Panels (a) and (b) show fluid flow in a circular path within a MB, i.e., a flow which allows bubble contents to circulate largely without being lost to the surround. Panels (c) and (d) show flow velocity above and within a bubble, with red a high flow and blue a low flow. These panels further demonstrate how MB contents are largely retained under low shear stress in our MBA™ products.