Hierarchical host-guest assemblies formed on dodecaborate-coated gold nanoparticles.

Undecahydro-mercapto-closo-dodecaborate (BSH), a purely inorganic cluster anion, serves as an unconventional stabilizing ligand for the preparation of gold nanoparticles (AuNPs). The BSH-capped AuNPs serve as nano-scaffolds, allowing for the creation of supramolecular architectures by using polycationic macrocyclic host molecules, through strong host-guest complexation. An amphiphilic calixarene (CX) forms first mono- and subsequently bi-layer assemblies on the BSH-AuNP surfaces depending on the CX concentration. The inorganic-organic hybrid materials, combined with host-dye displacement assays, serve as a chemosensing ensemble for negatively charged molecules, including DNA.