Adsorption behavior of temozolomide, carmustine, procarbazine, and lomustine anticancer drugs on zinc oxide nanocage: A DFT study

The adsorption behavior of zinc oxide (Zn12O12) nanocage toward delivering the temozolomide (TMZ), carmustine (CM), procarbazine (PR), and lomustine (LO) anticancer drugs was herein investigated utilizing the density functional theory (DFT) method. The emerging outcomes unveiled the potential efficiency of the Zn12O12 nanocage toward adsorbing the TMZ, CM, PR, and LO drugs and showed prominent negative values of binding energies (Delta E-bind) up to -14.69 kcal.mol(-1). Among the studied complexes, the Zn12O12-TMZ complex showed the most preferential Delta E-bind values in the gas and water phases compared to other studied complexes with values up to -14.69 and -12.88 kcal.mol(-1), respectively. The quantum theory of atoms in molecules announced the occurrence of the adsorption process between the Zn12O12 nanocage and anticancer drugs via polar covalent interactions and electrostatic interactions. Based on frontier molecular orbital theory affirmations, the electronic parameters of Zn12O12 nanocage changed preferentially upon adsorption of the studied drug within the most stable configurations. Moreover, the Zn12O12-drug complexes exhibited short recovery times for drug desorption from the nanocage. The results clearly confirmed that the Zn12O12 nanocage is an ideal candidate for the highly efficient development of anticancer TMZ, CM, PR, and LO drug carriers.