Stimuli-Responsive Cucurbit[7]uril-Mediated BSA Nanoassembly for Uptake and Release of Doxorubicin.

We report the construction of a non-toxic nanoassembly of bovine serum albumin (BSA) protein and the cucurbit[7]uril macrocycle as well as its stimuli-responsive breakage with adamantylamine or pH, which restores the protein structure and recognition properties. The assembly showed efficient loading and controlled release of a standard drug, doxorubicin (DOX), and the same was validated in live cells. The cell viability studies documented that the DOX-loaded assembly mask the cytotoxicity of DOX and the toxicity can be revived at the target on demand, triggering its therapeutic activation. This is found to be more effective in the cancer cells. In addition, such host-assisted protein assemblies are also highly promising for stabilizing/protecting the native protein structure, a viable approach to prevent/inhibit protein misfolding and aggregation.