Here, physical chemistry properties of the inclusion complexes of some alkaloids and cyclopentano-cucurbit[8, 10]urils (Cy-CB[8, 10]) were investigated via molecular dynamic (MD) simulations and density functional theory (DFT) calculations. The possibility of the heterojunction formation between cyclopentano-cucurbit[8, 10]urils and graphene oxide was investigated via MD simulation. Based on the results, an effective role of graphene oxide on the encapsulation complex formation, especially in the presence of codeine and morphine was confirmed. DFT (M06-2X) and DFT-D3 (M06-2X-D3) functionals were applied for geometry optimization of the complexes. To have an insight into the atomic level, different analyses, such as natural bond orbital and quantum theory of atoms in molecule analyses were applied and discussed. DFT results confirm that Cy-CB[8] makes a stronger interaction with alkaloids in comparison with Cy-CB[10]. Thermodynamic studies show that the complexation process of codeine inside Cy-CB[n] is more favorable than other complexes. Moreover, energy analysis showed that the van der Walls part plays an important role in alkaloid stabilization inside the Cy-CB[n] cavity.

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