In 1994, Jansen, Berg, and Meijer reported the encapsulation of guest molecules into a dendritic box. The study describes the synthesis of dendritic boxes based on poly(propyleneimine) dendrimers with 64 amine end groups, which were modified with a chiral shell of protected amino acids. Nuclear magnetic resonance and optical data showed that a dense, solid-phase shell was formed. Guest molecules were captured within the internal cavities of the boxes when constructed in the presence of guest molecules. The diffusion of guest molecules out of the boxes was extremely slow due to the close packing of the shell. These dendritic containers, with dimensions of 5 nanometers, had physically locked-in guest molecules and were characterized spectroscopically. Dendrimers are highly branched, three-dimensional macromolecules with a defined number of generations and functional end groups. Their unique properties have led to the synthesis of various structures, including unimolecular micelles and mesostructures. The concept of topological trapping by core-shell molecules is based on the idea that the space available for the next generation of dendrimers is insufficient to accommodate all atoms, leading to a specific stoichiometry. The study demonstrates the synthesis of dendritic boxes with internal cavities and dense outer shells, which can encapsulate guest molecules. The synthesis of the rigid shell involved the modification of cascade polyamines with bulky groups, such as amino acid derivatives. The resulting dendrimers were purified based on solubility differences. The shell was shown to be solid-phase in nature, with minimal molecular motion. NMR and other spectroscopic techniques were used to elucidate the structure of the dendrimers. The study also demonstrated the encapsulation of various dye molecules into the dendritic box, with the dye molecules showing unique absorption and emission properties when encapsulated. The results suggest that the procedures described can be used to produce unimolecular compartmented structures where guest molecules are physically locked in and diffusion out of the box is extremely slow. The study also highlights the potential applications of these structures, such as fluorescent markers for nanoscale pores and controlled drug delivery. The findings contribute to the understanding of the stability and behavior of dendritic structures and their potential in various scientific and technological applications.In 1994, Jansen, Berg, and Meijer reported the encapsulation of guest molecules into a dendritic box. The study describes the synthesis of dendritic boxes based on poly(propyleneimine) dendrimers with 64 amine end groups, which were modified with a chiral shell of protected amino acids. Nuclear magnetic resonance and optical data showed that a dense, solid-phase shell was formed. Guest molecules were captured within the internal cavities of the boxes when constructed in the presence of guest molecules. The diffusion of guest molecules out of the boxes was extremely slow due to the close packing of the shell. These dendritic containers, with dimensions of 5 nanometers, had physically locked-in guest molecules and were characterized spectroscopically. Dendrimers are highly branched, three-dimensional macromolecules with a defined number of generations and functional end groups. Their unique properties have led to the synthesis of various structures, including unimolecular micelles and mesostructures. The concept of topological trapping by core-shell molecules is based on the idea that the space available for the next generation of dendrimers is insufficient to accommodate all atoms, leading to a specific stoichiometry. The study demonstrates the synthesis of dendritic boxes with internal cavities and dense outer shells, which can encapsulate guest molecules. The synthesis of the rigid shell involved the modification of cascade polyamines with bulky groups, such as amino acid derivatives. The resulting dendrimers were purified based on solubility differences. The shell was shown to be solid-phase in nature, with minimal molecular motion. NMR and other spectroscopic techniques were used to elucidate the structure of the dendrimers. The study also demonstrated the encapsulation of various dye molecules into the dendritic box, with the dye molecules showing unique absorption and emission properties when encapsulated. The results suggest that the procedures described can be used to produce unimolecular compartmented structures where guest molecules are physically locked in and diffusion out of the box is extremely slow. The study also highlights the potential applications of these structures, such as fluorescent markers for nanoscale pores and controlled drug delivery. The findings contribute to the understanding of the stability and behavior of dendritic structures and their potential in various scientific and technological applications.