Investigating Effect of Dimensional Variance on Separation of Glomerular Ultrafiltrate in a Microfluidic Environment

This study investigates the impact of microchannel geometrical parameters on the separation of glomerular ultrafiltrate in a non-cell-based microfluidic device. The analysis focuses on the device's ability to selectively separate plasma from other blood components, considering parameters such as the radius of curvature at the channel junction, the side channel angle, and the membrane pore shape. Among the configurations tested, a channel junction with radii of curvature Rc1=5 μm and Rc2=0 μm achieved the highest separation efficiency. A straight, perpendicular side channel outperformed other angular variations, while cylindrical membrane pores promoted laminar flow with minimal turbulence and shear stress, enhancing ultrafiltrate separation. The glomerular filtration fraction was observed to be around 20%, closely matching values reported for the human glomerulus under whole blood conditions. The proposed device functions as a glomerular ultrafiltration unit and can potentially be integrated with other modules to develop a complete artificial kidney. This numerical study provides insights into key microchannel design parameters that influence separation efficiency. Moreover, as the device does not rely on cultured cells, it is expected to have a longer operational lifespan and reduced maintenance costs by eliminating the need for cell cultivation.