Tiny cages, big impact: A DFT investigation of 5-fluorouracil adsorption on Mg-, Si-, and Zn-doped B40 borospherene for drug delivery

Abstract

Properties of a ‘bucky-ball’ type macromolecule called borospherene having forty Boron atoms (B₄₀) are computationally investigated using B3LYP functions in GAUSSIAN 16 as a potential drug delivery nano-carrier for anticancer drug 5-Fluororacil (5FU). Adsorption energies are compared for three positions of 5FU on the borospherene by taking advantage of the heptagonal and hexagonal edges of the B₄₀ cage and initially placing O-atom and N-atom of 5FU 1.5Å away from the involved B atom. The B₄₀ cage is also doped with single-atom metal/metalloids namely Mg, Si, and Zn, with observed promising adsorption of the 5FU drug. Calculated values of formation energies show that SiB₄₀ forms more readily among the MB₄₀ cages, followed by MgB₄₀ and ZnB₄₀. Inspecting bond lengths, HOMO-LUMO energy gap values, and adsorption energies of MB₄₀-5FU clusters point to MgB₄₀ as the more promising carrier candidate for drug delivery in targeted cancer treatment.