Supramolecular assemblies with macrocyclic hosts: applications in antibacterial activity

This review article focuses on the supramolecular assemblies fabricated through host-guest interaction using macrocycles such as cyclodextrins, calixarenes and cucurbiturils as hosts. Though several review articles have appeared on such host-guest assemblies having importance in controlled drug-delivery, fluorescence on-off sensors, catalysis etc., not much attention has been given to collect their potential applications in antibacterial activity. In this article we have mainly discussed the concepts, strategies and applications to enhance the antibacterial activity of different assemblies with some of the well-established antibacterial drugs/agents. The enhanced antibacterial activity of hydrogel, gelatin composite film, bismuth oxide nanoparticles and sanguinarine drug in the presence of cyclodextrins have been described in detail. The mechanism for the improved antibacterial activity of calixarene-capped nanoparticles, calixarene-complexed antibiotics and stimuli-responsive calixarene-based nanoassemblies for NO release was discussed. The enhanced photosensitizing effect of cucurbituril (CB) complexed porphyrins and their stimuli-responsive control over its antibacterial activity and the photothermal therapy has been elaborated. The effect of augmented antibacterial activity of CB-encapsulated drugs have also been given emphasis as they are promising for long-acting antibiotics.