Estudo teórico da interação entre Apigenina e Nanotubo de Nitreto de Boro como material promissor com Nanocarreadores

Abstract

Computational chemistry methods were employed to evaluate the interaction between apigenin (APG), a flavonoid with known therapeutic properties, and boron nitride nanotubes (BNNTs), as well as to investigate the potential of BNNTs as nanocarriers. BNNT models were generated by rolling a hexagonal h-BN sheet using shell bash algorithms. The geometries were initially optimized using the PM7 method, with hydrogenated termini to minimize edge effects, and subsequently subjected to Density Functional Theory (DFT) calculations employing the B3LYP functional and the 6-31G(d) basis set with GD3 dispersion correction. Simulations were performed both in vacuum and in an aqueous environment, using the Polarizable Continuum Model (PCM) to account for the dielectric effect of water. The encapsulation of APG within the BNNT preserved the stability of the system in both media, with negative binding energies indicating favorable interactions. Solvation enthalpies (–10.93 kcal/mol for APG, –27.45 kcal/mol for BNNT, and –30.65 kcal/mol for the complex) indicate an approximately threefold increase in the solubility of APG. The band gap was used to assess reactivity and stability, yielding values of 6.11 eV for BNNT, 4.18 eV for APG, and 4.09 eV for the complex, indicating preservation of the electronic properties of the drug. Molecular descriptors revealed an increase in electrophilic character, suggesting enhanced affinity toward nucleophilic sites of biomolecules, such as those present on tumor cell surfaces, which typically exhibit higher superficial electron density. Molecular dynamics simulations demonstrated the stability of the encapsulated drug over 50 ns, supported by analyses of center-of-mass distance, root mean square fluctuation (RMSF), and radius of gyration, which confirmed the structural integrity of the system. Binding free energy calculations using the MM/PBSA method revealed that van der Waals interactions play a central role in stabilizing the APG–BNNT complex. Overall, these results indicate that BNNTs are promising nanocarriers capable of enhancing the solubility and stability of APG without altering its electronic structure, reinforcing the potential of the APG–BNNT system for the development of nanopharmaceuticals and controlled drug delivery systems.