Near-infrared light-responsive supramolecular nanovalve based on mesoporous silica-coated gold nanorods

We constructed a novel cancer theranostic hybrid platform, based on mesoporous silica-coated gold nanorods (AuNR@MSN) gated by sulfonatocalix[4] arene (SC[4]A) switches, for bio-friendly near-infrared (NIR) light-triggered cargo release in a remote and stepwise fashion. The advantages of supramolecular switches, mesoporous silicas, and AuNRs were combined in one drug delivery system. Mesoporous silicas coated on AuNRs guarantee a high drug payload and can be easily post-functionalized. Significantly, the plasmonic heating from the NIR light-stimulated AuNR cores can decrease the ring-stalk binding affinity, leading to the dissociation of SC[4]A rings from the stalks, thus opening the nanovalves and releasing the cargos. The NIR light-responsive mechanized AuNR@MSN offers exciting prospects for non-invasive controlled drug delivery, being more effective and safer than other techniques.