Pillar[5]arene stabilized gold nanoparticles for the enhanced light-triggered nitric oxide release with antibacterial and antibiofilm activities

The reactivity of guests confined in well-defined host cavities act significantly different from that in bulk systems. In this work, pillar[5]arene not only works as a stabilizer for the fabrication of gold nanoparticles, but also act as an accelerator for the enhanced photo-triggered release of gaseous nitric oxide (NO) from encapsulated NO donor. The host-guest complex can dramatically improve the photoactivity of loaded guest molecule to generate antibacterial NO molecules through the confinement effect of pillar[5]arene cavity. The synergistic phototriggered localized NO release and photo-thermal effect of host-guest complex demonstrated impressive antibacterial behaviors against Gram-negative bacterial strain Escherichia coli, Gram-positive bacterial strain Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. Moreover, this biocompatible photoresponsive complex can also inhibit bacterial biofilm formation and disrupt the pre-existing biofilms.