DFT and solvent-phase insights into nitrosourea adsorption on AlN, GaN and their in-plane heterostructure (AlN/GaN) nanosheets

Cancer is the second most common cause of death worldwide and its frequency is rising as the population grows. Nanotechnology has become a viable strategy for targeted cancer therapy in order to overcome these constraints in drug delivery. This study focuses on the adsorption behavior, electrical characteristics and drug-carrier interactions of the anticancer drug nitrosourea (NU) with pristine aluminum nitride (AlN) and gallium nitride (GaN) nanosheets along with their in-plane heterostructures (AlN/GaN (H1) and GaN/AlN (H2)) as efficient and selective potential nanocarriers for the delivery using density functional theory (DFT) in both air and water media. Our calculations showed that the NU adsorbed on AlN, AlN/GaN (H1), GaN and GaN/AlN (H2) with adsorption energies of -0.94, -0.74, -0.72, and -0.64 eV in air media and -0.75, -0.76, -0.51, and -0.36 eV in water media for the most stable complexes, respectively. After adsorption, the HOMO-LUMO energy gaps were reduced to be 3.84 to 1.87, 3.54 to 1.15, 3.37 to 2.07 and 3.54 to 2.18 eV for these nanosheets. The reduced HOMO-LUMO energy gap enhances the conductivity of the nanosheets and improved their applicability for electronic drug detection. The increased dipole moments and work function changes, mainly in water media following NU adsorption, indicate improved polarity and solubility. Furthermore, reactivity and stability were assessed using Conductor-like Screening Model (COSMO) surface and quantum molecular descriptor studies. According to our research, AlN and GaN based nanomaterials showed great promise as effective and selective NU carriers. Among them AlN in state 2 indicated their potential as effective nanocarriers for nitrosourea by exhibiting the best adsorption energy, electronic modulation and structural integrity.