Micelles via self-assembly of amphiphilic beta-cyclodextrin block copolymers as drug carrier for cancer therapy.

We developed intelligent, star-shaped amphiphilic β-cyclodextrin (β-CD) co-polymer nanocarriers to circumvent the poor drug loading and water-solubility of β-CD. The secondary hydroxyl groups of β-CD were methylated to improve solubility, and the primary hydroxyl groups were conjugated with mPEG-b-PCL-SH through disulfide linkage to amplify the hydrophobic cavity and enhance the stability of the nanocarrier. A series of amphiphilic β-CD block copolymers (CCPPs) differing in molecular weights were synthesized that could self-assemble into core-shell nanospheres measuring 50-70 nm in water. The different CCPP carriers were screened for their drug loading, encapsulation and release efficiencies, and CCPP-2 showed the highest drug loading capacity of 31.9% by weight. These nanocarriers accumulated at the tumor site through the EPR effect and released the drug in a controlled manner in the reductive tumor microenvironment, with negligible premature leakage and side effects. Therefore, CCPP-2 shows significant potential as a smart and efficient nanovehicle for anticancer drug delivery.