Theoretical study of glycoluril by highly symmetrical magnesium oxide Mg12O12 nanostructure: adsorption, detection, SERS enhancement, and electrical conductivity study

Using metal substrates that are nanoscale in size, surface-enhanced Raman scattering (SERS) is a technique for enhancing the Raman signal of biomolecules. Numerous industries including sensing materials, adsorption and medical devices, use nanomaterials like nanocages and nanoclusters. To discover a possible novel sensor platform involving a small metal cluster and a curved rigid substrate, we used density functional theoretical (DFT) simulations to explore the adsorption of glycoluril (GLC), a prospective drug intermediate, on a pure magnesium oxide cage (Mg₁₂O₁₂). This well defined cage was used as (i) an exact probable structure that could be used as well as (ii) a general model for MgO nanostructures. We also investigated the mono Al-doped Mg₁₂O₁₂ nanocage version Mg₁₁AlO₁₂. All computations were performed at the M06-2X level of theory. The GLC binds to the Mg₁₂O₁₂ nanocage by way of strong donor-acceptor interactions. The adsorption is releasing - 45.80 kcal mol^-1 of energy. Due to Al doping, the energy gap of GLC-Mg₁₁AlO₁₂ (1.91 eV) is reduced from that of GLC-Mg₁₂O₁₂ (4.28 eV) and hence there is an increase in electrical conductivity of GLC-Mg₁₁AlO₁₂. The electronic change in the nanocage's conductivity can be transformed into an electrical signal which can be used to detect the presence of the drug analyte. In addition, when a GLC molecule is present, the work function of the nanocage is also reduced. The MgO nanocage, we conclude, is a work function type as well as a possible electronic sensor for GLC drug detection. GLC desorption from the Mg₁₁AlO₁₂ surface recovers more quickly in comparison with Mg₁₂O₁₂ recovery time. The AIM and NCIs assessed in this study were performed to help analyze the electronic structures of the complexes. Our findings pave the possibility for Mg₁₁AlO₁₂ nanostructures to be used in drug recognition.