Mechanised lubricating silica nanoparticles for on-command cargo release on simulated surfaces of joint cavities.

We describe a type of supramolecular host-guest function silica nanoparticle activated by energy conversion from joint movement. The high coefficient of friction from damaged joints causes more energy conversion, weakening the surface host-guest interaction and resulting in target cargo release. Additionally, the hydrated layer on the nanoparticle surface plays a role in lubrication enhancement.