Size-Dependent Effective Diffusivity in Healthy Human and Porcine Joint Synovium.

Size-Dependent Effective Diffusivity in Healthy Human and Porcine Joint Synovium. Ann Biomed Eng. 2021 Jan 25;: Authors: Guang Y, Davis AL, McGrath TM, Pham CTN, Fitzpatrick JAJ, Setton LA Abstract Intra-articular drug delivery can be effective in targeting a diseased joint but is hampered by rapid clearance times from the diarthrodial joint. The synovium is a multi-layered tissue that surrounds the diarthrodial joint and governs molecular transport into and out of the joint. No models of drug clearance through synovium exist to quantify diffusivity across solutes, tissue type and disease pathology. We previously have developed a finite element model of synovium as a porous, permeable, fluid-filled tissue and used an inverse method to determine urea's effective diffusivity (Deff) in de-vitalized synovium explants.22 Here we apply this method to determine Deff from unsteady diffusive transport of model solutes and confirm the role of molecular weight in solute transport. As molecular weight increased, Deff decreased in both human and porcine tissues, with similar behavior across the two species. Unsteady transport was well-described by a single exponential transient decay in concentration, yielding solute half-lives (t1/2) that compared favorably with the Deff determined from the finite element model fit. Determined values for Deff parallel prior observations of size-dependent in vivo drug clearance and provide an intrinsic pa...
Source: Annals of Biomedical Engineering - Category: Biomedical Engineering Authors: Tags: Ann Biomed Eng Source Type: research