Adsorption and desorption behaviors of hydroxyurea drug on delivery systems of B12N12 fullerene and its Al-, Si- and P-dopings from theoretical perspective

Systematic exo-endo encapsulation of hydroxyurea (HU) by Cu, Ag, and Au-doped gallium nitride nanotubes (GaNNT) for smart therapeutic delivery

Similar to the more well-known carbon nanotubes, gallium nitride nanotubes (GaNNT) are among the materials that scientists have found to be extremely helpful in transporting drugs and to provide significant potential for multi-modal medical therapies. Here, the potential of Cu, Ag, and Au-doped GaNNT for smart delivery of the anticancer medication hydroxyurea (HU) was extensively investigated employing quantum chemical analysis and density functional theory (DFT) computation at the B3LYP-GD3BJ/def2-SVP level of theory. The systematic approach used in this study entails examining the exo (outside)-and endo (inside) loading of HU utilizing the investigated nanotubes in order to understand the adsorption, sensing processes, bonding types, and thermodynamic properties. Results of the HOMO-LUMO studies show that metal-doped GaNNTs with the hydroxyurea (HU) at the endo - interaction of the drug of the nanotube produced more reduced energy gaps (0.911-2.039 eV) compared with metal-doped GaNNTs complexes at the outside - interaction of the drug on the nanotube (2.25-3.22 eV) and as such reveal their suitability for use as drug delivery materials. As observed in the endo-interaction of HU adsorptions in the tubes, HU_endo_Au@GaNNT possessed the highest adsorption energy values of -118.716 kcal/mol which shows the most chemisorption between the surfaces and the adsorbate while for HU_exo_Ag@GaNNT is -97.431 kcal/mol for the highest exo-interactions. These results suggest that HU drug interacted inside the Ag, Au, and Cu doped GaNNT will be very proficient as a carrier of the HU drug into bio systems. These results are along with visual studies of weak interactions, thermodynamics, sensor, and drug release mechanisms suggest strongly the endo-encapsulation of HU as the best mode for smart drug delivery.

Heteroatom (B, N, P, and S)-Doped Cyclodextrin as a Hydroxyurea (HU) Drug Nanocarrier: A Computational Approach

Theoretical examination of hydroxyurea adsorption capabilities toward the cyclodextrin surface for proper drug delivery systems was carried out utilizing DFT simulations. The study aims to assess the efficacy of doped cyclodextrin (doped with boron, nitrogen, phosphorus, and sulfur atoms) in increasing its stability and efficiency in intermolecular interactions, hence facilitating optimal drug delivery. The adsorption energies were found to follow a decreasing order of B@ACD-HU>N@ACD-HU>P@ACD-HU>S@ACD-HU with energies of -0.046, -0.0326, -0.015, and 0.944 kcal/mol, respectively. The S@ACD-HU complex, unlike previous systems, had a physical adsorption energy. The N@ACD-HU and B@ACD-HU complexes had the shortest bond lengths of 1.42 Å (N122-C15) and 1.54 Å (B126-C15), respectively. The HOMO and LUMO values were also high in identical systems, -6.367 and -2.918 eV (B@ACD-HU) and -6.278 and -1.736 eV (N@ACD-HU), respectively, confirming no chemical interaction. The N@ACD-HU has the largest energy gap of 4.54 eV. For the QTAIM analysis and plots, the maximum electron density and ellipticity index were detected in B@ACD-HU, 0.600 au (H70-N129) and 0.8685 au (H70-N129), respectively, but N@ACD-HU exhibited a high Laplacian energy of 0.7524 a.u (H133-N122). The fragments' TDOS, OPDOS, and PDOS exhibited a strong bond interaction of greater than 1, and they had different Fermi levels, with the highest value of -8.16 eV in the N@ACD-HU complex. Finally, the NCI analysis revealed that the complexes were noncovalent. According to the literature, the van der Waals form of interactions is used in the intermolecular forces of cyclodextrin cavities. The B@ACD-HU and N@ACD-HU systems were more greenish in color with no spatial interaction. These two systems have outperformed other complexes in intermolecular interactions, resulting in more efficient drug delivery. They had the highest negative adsorption energies, the shortest bond length, the highest HOMO/LUMO energies, the highest energy gap, the highest stabilization energy, the strongest bonding effect, the highest electron density, the highest ellipticity index, and a strong van der Waals interaction that binds the drug and the surface together.

Adsorption of Chlormethine Anti-Cancer Drug on Pure and Aluminum-Doped Boron Nitride Nanocarriers: A Comparative DFT Study

The efficacy of pure and aluminum (Al)-doped boron nitride nanocarriers (B12N12 and AlB11N12) in adsorbing Chlormethine (CM), an anti-cancer drug, was comparatively dissected by means of the density functional theory method. The CM∙∙∙B12N12 and ∙∙∙AlB11N12 complexes were studied within two configurations, A and B, in which the adsorption process occurred via N∙∙∙ and Cl∙∙∙B/Al interactions, respectively. The electrostatic potential affirmations confirmed the opulent ability of the studied nanocarriers to engage in delivering CM via two prominent electrophilic sites (B and Al). Furthermore, the adsorption process within the CM∙∙∙AlB11N12 complexes was noticed to be more favorable compared to that within the CM∙∙∙B12N12 analog and showed interaction and adsorption energy values up to -59.68 and -52.40 kcal/mol, respectively, for configuration A. Symmetry-adapted perturbation theory results indicated that electrostatic forces were dominant in the adsorption process. Notably, the adsorption of CM over B12N12 and AlB11N12 nanocarriers exhibited predominant changes in their electronic properties. An elemental alteration was also revealed for the softness and hardness of B12N12 and AlB11N12 nanocarriers before and following the CM adsorption. Spontaneity and exothermic nature were obviously observed for the studied complexes and confirmed by the negative values of thermodynamic parameters. In line with energetic manifestation, Gibbs free energy and enthalpy change were drastically increased by the Al doping process, with values raised to -37.15 and -50.14 kcal/mol, respectively, for configuration A of the CM∙∙∙AlB11N12 complex. Conspicuous enhancement was noticed for the adsorption process in the water phase more than that in the gas phase and confirmed by the negative values of the solvation energy up to -53.50 kcal/mol for configuration A of the CM∙∙∙AlB11N12 complex. The obtained outcomes would be the linchpin for the future utilization of boron nitride as a nanocarrier.