We report on hollow shell-shell nanogels with two polymer shells that have different volume phase
transition temperatures. By means of small angle neutron scattering (SANS) employing contrast
variation and molecular dynamics (MD) simulations we show that hollow shell-shell nanocontainers
are ideal systems for controlled drug delivery: The temperature responsive swelling of the inner shell
controls the uptake and release, while the thermoresponsive swelling of the outer shell controls the
size of the void and the colloidal stability. At temperatures between 32°C < T < 42°C, the hollow
nanocontainers provide a significant void, which is even larger than the initial core size of the template, and they possess a high colloidal stability due to the steric stabilization of the swollen outer shell. Computer simulations showed, that temperature induced switching of the permeability of the inner shell allows for the encapsulation in and release of molecules from the cavity.