A DFT investigation on theranostic potential of alkaline earth metal doped phosphorenes for ifosfamide anti-cancer drug

Cancer is one of the leading causes of human mortality and a theranostics strategy is essential for its effective treatment. Density function theory (DFT) simulations were executed to examine the drug delivery, photothermal potential, and photoimaging guided cancer diagnostic potential of pristine and alkaline earth metal (M=Be, Mg, and Ca) doped phosphorenes (M-PH). The topological, electronic, and thermodynamic descriptors of M@PH and Ifosfamide (IFO) loaded systems (IFO@M-PH) were calculated. The oxygen atoms of IFO coordinated with the doped M-PH carrier. The adsorption process was exothermic and hence spontaneous. A higher adsorption energy was found for IFO@M-PH systems compared to undoped system. The polarity of the drug-carrying system is increased after doping which is favorable for effective in vivo drug flow. The HOMO-LUMO and natural bond orbital (NBO) analyses revealed that doping facilitated the charge transfer from drug to phosphorene. The quantum theory of atoms in molecules (QTAIM) and non-covalent interaction (NCI) studies show the presence of weak non-covalent interactions among the drug and substrate, supporting the effective drug release. The excited-state calculations for drug loaded complexes show the shifting of lambda(max) from 434 nm to Near-Infrared (NIR) region. This supported IFO@M-PH as a potential candidate for photothermal therapy and photoimaging guided cancer diagnostic.