Facile construction of pH-responsive nanocarrier based on host-guest interactions chemistry for triggered drug delivery

The objective of the current study was to design and synthesize a well-defined pH-sensitive system based on poly(2-hydroxyethyl methacrylate)-g-(poly(epsilon-caprolactone)-benzimidazole): beta-cyclodextrin-star-(poly(2-(dimethylamino)ethyl methacrylate))7 [PHEMA-g-(PCL-BM): beta-CD-star-(PDMAEMA)7] via the host-guest interaction and its self-assembled nanomicelles for the administration of hydrophobic drugs. The molecular structures of the synthesized materials were characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance and gel permeation chromatography. The supramolecule formed by host-guest interaction between beta-CD- star-(PDMAEMA)7, and PHEMA-g-(PCL-BM) could self-assemble in an aqueous environment to form spherical nanomicelles. The morphology of the resultant micelles was investigated by field emission-scanning electron microscopy and transmission electron microscopy. Using dynamic light scattering, the average size of the micelles was obtained about 97.1 nm. Docetaxel (DTX), a model anticancer drug, was successfully loaded into the micelles via hydrophobic interactions with encapsulation efficiency of 82%. The biocompatibility of the DTX-loaded micelles was investigated based on breast cancer cell line (MCF-7) using MTT assay. Finally, DAPI staining and cellular uptake analysis confirmed that the micelles could be potentially used as a bioactive structure for cancer therapy.