Targeted Tumor Therapy Based on Nanodiamonds Decorated with Doxorubicin and Folic Acid

The fabrication of nanodiamond (ND)-based drug carriers for tumor-targeted drug delivery is described. The ND clusters with an average size of 52.84 nm are fabricated using a simple fluidic device combined with a precipitation method and then conjugated with folic acid (FA) and doxorubicin (Dox) via carbodiimide chemistry to obtain FA/Dox-modified ND (FA/Dox-ND) clusters. Cell culture experiments revealed that KB (folate receptor-positive) cells are preferentially ablated by FA/Dox-ND clusters compared to A549 (folate receptor-negative) cells. In vivo results revealed that FA/Dox-ND clusters are specifically accumulated in tumor tissues after intravenous injection into tumor-bearing mice, effectively reducing the volume of tumor. Based on these results, this study suggests that FA/Dox-ND clusters can be a good candidate as tumor-targeted nanovehicles for delivery of antitumor drug.