Cyclodextrin and folate functionalized polymer nanocarriers: Chain length dependent properties

Abstract

We report a series of β-cyclodextrin and folate-tethered poly(ethylene glycol) with various spacer chain lengths, prepared and characterized using spectroscopic methods. The size and morphology differ between nanoparticles made of polymers of different chain lengths. Smaller molecular weight polymers form web-like structures, whereas the larger ones form spherical nanostructures. The polymers' encapsulation mode of the anticancer drug camptothecin is investigated utilizing ROESY spectroscopy. Significant encapsulation efficiencies of above 90% are achieved by the nanoparticles having molecular weights of the poly(ethylene glycol) spacer viz., 9,000 and 12,000. A comparison of the camptothecin release rates, size and morphology, and the anticancer activity of the nanoparticles on MCF-7 and Vero cell lines are charted. We observed high efficacies of the PEG9000 and PEG12000-containing nanoparticles. Further, we inferred that a clear relationship between the anticancer activity of the nanoparticles exists with the polymer chain length-dependent morphological features, drug encapsulation mode, and the differences in the controlled release of the drug. The work throws new light on the desired parameters of polymeric nanocarriers functionalized with β-cyclodextrin and folate, which utilize the host: guest complexation, leading to effective drug delivery.