Design and analysis of microfluidic kidney-on-chip model: fluid shear stress based study with temperature effect

The flow in the nephron tubules regulates the blood homeostasis, secretion, excretion and reabsorption of solutes. Flow induces fluid shear stress (FSS) on walls of tubules which has substantial effect on kidney functioning. Modelling of FSS mimicking structures is critical for their optimization. In this paper, a compact structure for kidney-on-chip devices is proposed for exact reconstruction of FSS and temperature effect in tubules considering the nephron tubule dimensions for modelling. The proposed system is compartmentalized basically into three parts ultra filter, device structure and reactor. The FSS is analysed for different inflow rates, proving the proposed structure is helpful in balancing the tubuloglomerulo feedback system mimicking. The structure is analysed for different structural changes in benchmark FEM tool COMSOL Multiphysics to optimize it to suite the kidney-on-chip purpose. Pressure achieved at the cell site is 0.1 Pa, which is the pressure applied by FFS on kidney tubules cells. The temperature effect of the human body is considered and the findings are presented. Temperature has an inverse relationship with FSS. At absolute temperature the pressure is 9.7 Pa and reached 3.77 Pa at body temperature, showing a decrease in pressure. The reaction of sodium and calcium is presented to show common reabsorption happening the kidney. The fabrication process flow is implemented in Intellisuite tool which is incorporated here to indicate the device fabrication cost will be low. The proposed Kidney-on-Chip structure finds astounding results make it to use in potential transplantable devices.