Supramolecular purification of mono-adamantane mixtures via stabilized three-shell Matryoshka assemblies

The adamantane (Ad) core is widely used in pharmaceuticals, where it is regarded as a lipophilic "bullet" that enhances the bioactivity of Ad-bearing drugs. Despite its prevalence, little is known about its precise recognition modes within confined enzymatic active sites, and effective chromatographic strategies for the purification of mixtures of Ad derivatives remain limited. Herein, we report the supramolecular purification of mono-adamantane mixtures through the development of three-shell supramolecular Matryoshka assemblies, featuring an adamantane-cycloparaphenylene (CPP) host-guest adduct encapsulated within a tetragonal prismatic nanocage. This three-shell architecture operates via an all-in-one strategy: encapsulation is inefficient for either [8]CPP or diamondoids alone and occurs efficiently only when all three components are present simultaneously. A straightforward, solid-state filtration-redissolution protocol enables the purification of diamondoid mixtures with enhanced selectivity for amine-bearing adamantane derivatives. This approach demonstrates a high degree of supramolecular selectivity in complex diamondoid mixtures, potentially exceeding that of conventional chromatographic techniques.