Polymeric Encapsulation of Nanodiamond–Chemotherapeutic Complexes for Localized Cancer Treatment

Abstract

A diverse range of synthetic and natural nanoscale carriers in both particle and film/scaffold formats have been developed to enable controlled therapeutic release. Examples of these systems include metallic nanoparticles, polymer–protein conjugates, liposomes, micelles, dendrimers, polyelectrolyte films, copolypeptides, carbon nanotubes, etc. Nanodiamonds (NDs), in particular, possess several advantageous properties that make them suitable for advanced drug delivery while also remaining biocompatible. We have previously developed a method of functionalizing aqueous solubilized NDs of diameter 2–8 nm with doxorubicin (DOX), a clinically relevant chemotherapeutic capable of inducing potent DNA fragmentation and cellular apoptosis. This work has realized a scalable approach toward the fabrication of ND-embedded polymer microfilms for localized and sustained drug elution for post-operative chemotherapy. Due to their high surface-area-to-volume ratio and noninvasive dimensions, NDs are capable of extremely high loading capacities of therapeutic compounds. In addition, we have demonstrated the capability of ND binding with a broad range of charged therapeutic molecules via physical interactions due to their inherent surface charge properties. NDs are also biologically stable and appear to be non-toxic, which prevents adverse stressful/inflammation-inducing cellular reactions in the event that they are dispersed throughout the body for either systemic or more localized release activity. The combination of these properties in one system makes the NDs promising platforms for slow-release therapeutics to treat a broad array of physiological disorders (e.g. cancer, heart disease, wound healing, etc.).