  The ability to design artificial micro/nanomachines able to perform
sophisticated tasks crucially depends on the understanding of their interaction
with biosystems and their compatibility with the biological environment. Here,
Janus colloids fuelled only by glucose and light were designed, which can
autonomously interact with cell-like compartments and trigger endocytosis. The
crucial role played by the far field hydrodynamic interaction arising from the
puller/pusher swimming mode and adhesion is evidenced. It is shown that a large
contact time between the active particle and the lipid membrane is required to
observe the engulfment of a particle inside a floppy giant lipid vesicle.
Active Janus colloids showing relatively small velocities and a puller type
swimming mode are able to target giant vesicles, deform their membranes and
subsequently get stably engulfed. An instability arising from the unbound
membrane segment is responsible for the transition between partial and complete
stable engulfment. These experiments shed light on the physical criteria
required for autonomous active particle engulfment in giant vesicles, which can
serve as general principles in disciplines ranging from drug delivery and
microbial infection to nanomedecine.
