A novel bioreducible and pH-responsive magnetic nanohydrogel based on β-cyclodextrin for chemo/hyperthermia therapy of cancer.

A new strategy for design and development of a magnetic "smart" drug delivery system (DDS) based on β-cyclodextrin (β-CD) and poly(2-ethyl-2-oxazoline) (PEtOx) was reported. For this purpose, a β-CD-(I) was acetylated, and then EtOx monomer was grafted onto the acetylated β-CD-(I) through cationic ring-opening polymerization followed by simultaneous crosslinking with amine-end capped FeO nanoparticles (FeO-NH NPs) and cystamine to produce a β-CD-g-(PEtOx)/FeO as a reduction- and pH-responsive magnetic DDS. The developed magnetic nanohydrogel was loaded with doxorubicin hydrochloride (Dox), and its drug loading and encapsulation efficiencies, as well as its pH- and reduction-triggered drug release behaviors were investigated. The anticancer activity of the formulated β-CD-g-(PEtOx)/FeO-Dox was investigated against MCF7 cells. According to the results, the formulated β-CD-g-(PEtOx)/FeO-Dox can be considered as an efficient and "smart" DDS for cancer therapy and diagnosis due to its high drug loading value (∼ 74 %), slow and stimuli-triggered drug release behavior, and acceptable magnetic properties.