Poly-cucurbituril nanoparticle host cavities (Poly-CB NP)

Poly-cucurbituril nanoparticle host cavities are synthetic supramolecular structures designed to encapsulate specific guest molecules within their macrocyclic framework. These cavities are formed by cucurbit[n]uril (CB[n]) units, which are barrel-shaped molecules composed of glycoluril monomers linked by methylene bridges (Kim et al., 2000, Chem. Soc. Rev.). The unique chemical environment of the cavity—featuring a hydrophobic interior and polar carbonyl groups at the portals—enables high-affinity binding to a wide range of cationic and hydrophobic drugs, such as neuromuscular blockers and certain chemotherapeutics (Webber & Langer, 2017, Chem. Soc. Rev.). When incorporated into nanoparticles or polymers, these host cavities serve as synthetic receptors or nanosponges that can be used for targeted drug delivery or as sequestration agents to neutralize toxins or reverse drug effects in vivo (Maity et al., 2021, J. Mater. Chem. B). Their therapeutic utility lies in their ability to modulate the pharmacokinetics and pharmacodynamics of guest molecules through non-covalent, reversible host-guest interactions. These systems are particularly noted for their potential to improve the safety profile of drugs by reducing systemic exposure and providing a controlled release mechanism (Zhang et al., 2014, Polym. Chem.).

Other names

Cucurbituril-based nanoparticlesSupramolecular cucurbituril polymersCB-nanoparticlesSynthetic cucurbituril receptorsCucurbit[n]uril host cavities

The mechanism involves supramolecular host-guest complexation, where a guest molecule (such as a drug or toxin) is encapsulated within the hydrophobic cavity of the cucurbituril macrocycle. This binding is stabilized by the hydrophobic effect and ion-dipole interactions between the guest's cationic groups and the carbonyl-fringed portals of the host (Kim et al., 2000, Chem. Soc. Rev.). In nanoparticle forms, these cavities provide high-capacity sequestration or controlled release of the guest (Maity et al., 2021, J. Mater. Chem. B).