Efficient Doxorubicin Delivery Using Deaggregated and Carboxylated Nanodiamonds for Cancer Cell Therapy

Abstract

In recent years, nanodiamonds (NDs) have been investigated as a promising candidate for drug delivery carrier due to a high biocompatibility and excellent physicochemical properties. However, uncontrolled aggregation of the as-prepared NDs often hinders their practical application. In this work, we report an effective drug delivery system based on the NDs through deaggregation and carboxylation for cancer cell therapy. The deaggregated NDs were responsible for enhanced dispersion stability and larger specific surface area. The subsequent carboxylation of the NDs sufficiently provided a strong chemical bonding between the NDs and doxorubicin (DOX) with high conjugation degree. The carboxylated ND-DOX conjugates showed a higher suppression ratio of Huh7 cell proliferation and the effect was remarkable at a longer incubation time, comparing to the free DOX and as-received ND-DOX conjugates. It is thus expected that the ND-based drug delivery system with a superior therapeutic efficacy can dramatically reduce essential dose of drugs and side effects for cancer cell therapy.