  Accurate delivery of small targets in high vacuum is a pivotal task in many
branches of science and technology. Beyond the different strategies developed
for atoms, proteins, macroscopic clusters and pellets, the manipulation of
neutral particles over macroscopic distances still poses a formidable
challenge. Here we report a novel approach based on a mobile optical trap
operated under feedback control that enables long range 3D manipulation of a
silica nanoparticle in high vacuum. We apply this technique to load a single
nanoparticle into a high-finesse optical cavity through a load-lock vacuum
system. We foresee our scheme to benefit the field of optomechanics with
levitating nano-objects as well as ultrasensitive detection and monitoring.
