organic solvents, precursors of block and graft copolymers,
template cores, or emulsion phases, thus avoiding the compli-
cated preparation schemes typically used for making hollow
nanospheres, and decreasing their potential toxicity so that
they may be used as drug carriers. We started with polymer±
monomer complexes formed between a biopolymer with ami-
no groups and an organic monomer with a carboxylic group.
Depending on the concentration of the two precursors in
aqueous solution, such polymer±monomer complexes can
form micelles through electrostatic interactions. Then, hollow
polymeric nanospheres could be obtained by polymerizing the
monomers inside the micelles.