Fast nanoparticle rotational and translational diffusion in synovial fluid and hyaluronic acid solutions

Abstract

Nanoparticles are under investigation as diagnostic and therapeutic agents for joint diseases, such as osteoarthritis. However, there is incomplete understanding of nanoparticle diffusion in synovial fluid, the fluid inside the joint, which consists of a mixture of the polyelectrolyte hyaluronic acid, proteins, and other components. Here, we show that rotational and translational diffusion of polymer-coated nanoparticles in quiescent synovial fluid and in hyaluronic acid solutions is well described by the Stokes-Einstein relationship, albeit with an effective medium viscosity that is much smaller than the macroscopic low shear viscosity of the fluid. This effective medium viscosity is well described by an equation for the viscosity of dilute polymer chains, where the additional viscous dissipation arises because of the presence of the polymer segments. These results shed light on the diffusive behavior of polymer-coated inorganic nanoparticles in complex and crowded biological environments, such as in the joint.

Field-Induced Assembly and Propulsion of Colloids

“…Research of self-propelling colloids is at a more fundamental stage compared to assembly, yet synthetic motile microparticles have outstanding potential in drug delivery, bioremediation, and also catalysis. In particular, we expect major advances in controlling motion within complex environments that are more realistic for applications such as in biomedical devices − and environmental remediation. − These include porous media, suspensions of macromolecules, and cellular environments. Further key research directions are distilled as follows: understand the role of thermodynamics vs kinetics in the assemblies formed by weak, competing field-induced interactions deconvolute the respective roles of particle shape, surface chemistry, and dispersing medium in field-induced colloidal phenomena find new methodologies to override stochastic Brownian forces and achieve organized active motion at the submicron scale by coupling multiple electromagnetic fields develop new field-induced colloidal platforms that respond to environmental cues and spontaneously self-regulate their structural and temporal characteristics expand the domain of fundamental active matter research to advanced materials capable of performing sophisticated functions such as energy transfer and mechanical work at the nanoscale …”

Ferrofluids and bio-ferrofluids: looking back and stepping forward

“…The analysis of the scattering curves in this case is the direct way to find out the size distribution of quasi-spherical magnetic cores (see recent examples in ref. 228, 309 and 311–313). In case when polydispersity is small, peculiarities in the SAXS curves (fringe like behavior) make it possible to conclude about the morphology of nanoparticles.…”

Hyaluronic Acid‐Based Injectable Hydrogels for Wound Dressing and Localized Tumor Therapy: A Review

“…It is an integral part of the extracellular matrix (ECM) and is widely present in connective tissues, dermis layers, and synovial joint fluids. [ 10–12 ] Apart from its excellent hydrophilicity, nontoxicity, and viscoelastic properties, HA shows superior biological functions including skin moisturization, [ 13 ] tissue repair, [ 14 ] antiwrinkle property, [ 15 ] inflammation regulation, [ 16 ] wound healing effect, [ 17 ] and cancer prognosis. [ 18 ] Meanwhile, the disaccharide units of HA possess a carboxyl, hydroxyl, and N ‐acetyl group, which can be reacted with different functional groups for crosslinking.…”