Figure 5.

Synovial fluid impacts the ability of nanomaterials to enter the cartilage matrix. Here, nanomaterials were composed of a poly(lactide-co-glycolide) core with polyvinyl alcohol and/or didodecyldiamonium bromide to create an anionic or cationic surface charge, respectively. (A) When the articular surface of bovine cartilage explants were exposed to such particles in a suspension of saline or synovial fluid, the amount of cationic particles significantly reduced but anionic particles remained unchanged. (B) Fluorescence of the particles shows that penetration was reduced for cationic particles when synovial fluid was included. NPs = nanoparticles; ** p < 0.01 (anionic vs. cationic NPs); β p < 0.01 (saline vs synovial fluid). [110] Adapted with permission from Molecular Pharmaceutics. Copyright 2017 American Chemical Society.