Developing a simple box–behnken experimental design on the removal of doxorubicin anticancer drug using Fe₃O₄/graphene nanoribbons adsorbent

This paper aims to develop a Box–Behnken experimental design system to optimize the removal process of doxorubicin anticancer drugs. For this goal, Fe₃O₄/graphene nanoribbons was selected as adsorbent and removal of doxorubicin anticancer drug optimized using Box–Behnken experimental design with a selection of four effective factors. A three-level, four-factor Box–Behnken experimental design was used to assess the relationship between removal percentage as a dependent variable with adsorption weight (0.0015–0.01 mg), pH (3–9), temperature (15–45 °C) and time (1–15 min) as independent variables. Optimized condition by Behnken experimental design (pH = 7.36; time = 15 min; adsorbent weight = 0.01 mg and temperature = 29.26 °C) improved removal of doxorubicin anticancer drug about 99.2% in aqueous solution. The dynamic behavior, adsorption properties and mechanism of doxorubicin molecule on Fe₃O₄/graphene nanoribbon were investigated based on ab initio molecular dynamics (AIMD) simulations and density functional theory calculations with dispersion corrections. A closer inspection of the adsorption configurations and binding energies revealed that π-π interactions were the driving force when the doxorubicin molecule adsorbed on Fe₃O₄/graphene nanoribbon. The observed negative adsorption energy signifies a favourable and exothermic adsorption process of the various adsorbate-substrate systems. Besides, AIMD and phonon dispersion calculations confirm the dynamic stability of Fe₃O₄/graphene nanoribbon.