Adsorption Tendency of Boron Oxide (B₂₄O₂₄) Nanocarrier toward Some Nucleobases and Their Nucleoside-Based Anticancer Drugs: A Comparative Density Functional Theory Study

In the current study, the adsorption potential of the B₂₄O₂₄ nanocarrier toward some nucleobases (NBs) and their nucleoside-based anticancer drugs was investigated based on density functional theory (DFT) calculations. The tendency of B₂₄O₂₄ to adsorb guanine (NB-G), adenine (NB-A), and uracil (NB-U) was investigated and comparatively addressed with thioguanine (TG), mercaptopurine (MP), and fluorouracil (FU) anticancer drugs. The potent adsorption process within NB/drug···B₂₄O₂₄ complexes was verified through the negative interaction (<i>E</i> _int) and adsorption (<i>E</i> _ads) energy values. In particular, NB···B₂₄O₂₄ complexes exhibited more negative <i>E</i> _int values compared to drug···B₂₄O₂₄ analogs with values up to -56.47 and -51.93 kcal/mol, respectively. The dominant role of the electrostatic forces in the total interactions within the NB/drug···B₂₄O₂₄ complexes was affirmed based on symmetry-adapted perturbation theory analysis. Noncovalent interaction analysis thoroughly characterized the intermolecular interactions within the studied NB/drug···B₂₄O₂₄ complexes. The substantial effect of water on NB/drug···B₂₄O₂₄ complexes was also noticed by means of favorable adsorption and solvation energies. In the scope of thermodynamic parameters, the spontaneous and exothermic nature of the studied NB/drug···B₂₄O₂₄ complexes was affirmed. Electronic analyses affirmed that the adsorption process of the studied NBs and drugs substantially affected the electronic nature of B₂₄O₂₄. Further, IR and Raman spectra verified the occurrence of the studied adsorption within NB/drug···B₂₄O₂₄ complexes. Based on the calculated recovery time values, the release of the studied NBs and drugs from the surface of B₂₄O₂₄ at the target site was verified. Overall, the results offered in-depth insights into the promising biomedical applications of B₂₄O₂₄, especially in the targeted delivery of NBs and anticancer drugs.