B 24 N 24 fullerene as a carrier for 5-fluorouracil anti-cancer drug delivery: DFT studies.

It has been previously indicated that BN nanostructures may be nontoxic and biocompatible. Here the potential application of a B24 N24 is explored as a drug delivery system for anti-cancer 5-fluorouracil based on the density functional theory. This drug prefers to attach via its oxygen atoms to the B atoms of the cluster with adsorption energy about -11.90kcalmol-1 based on the dispersion corrected B3LYP level of theory. To make the cluster more appropriate for drug delivery, we replaced a B atom by Si or Al atom to improve the interaction strength. The calculated adsorption energies are about -50.13 and -34.19kcalmol-1 for Al and Si doped BN clusters, respectively. It was found that, in addition to the more negative adsorption energy, the electronic properties of Al-doped BN are significantly sensitive to the drug adsorption. Also, a drug release mechanism is proposed, indicating that in the low pH of the cancer cells the drug and BN cluster are considerably protonated, thereby separating the drug from the surface of the cluster.