Boron Nitride Nanoparticles with a Petal-Like Surface as Anticancer Drug-Delivery Systems.

Nanoparticles (NPs) have a great potential as nanosized drug-delivery carriers. Such systems must safely deliver the drug to the site of the tumor without drug leakage, effectively penetrate inside cancer cells, and provide intracellular drug release. Herein we developed an original and simple method aimed at the fabrication of spherical boron nitride NPs (BNNPs), 100-200 nm in diameter, with peculiar petal-like surfaces via chemical vapor deposition. Such structures were found to be able to absorb a large amount of antitumor drug-killing tumor cells. They revealed low cytotoxicity and rapid cellular uptake. BNNPs were saturated with doxorubicin (DOX) and then dispersed. The BNNPs loaded with DOX (BNNPs-DOX) were stable at neutral pH but effectively released DOX at pH 4.5-5.5. MTT assay and cell growth testing showed that the BNNPs-DOX nanocarriers had been toxic for IAR-6-1 cells. BNNPs loaded with DOX penetrated into the neoplastic IAR-6-1 cells using endocytic pathways, and then DOX released into the cytoplasm and cell nuclei and resulted in cell death.