We study the structures, interaction energies, and vibrational spectra of the complexes of two drug molecules (lamivudine and tegafur) with pristine MoS2, as well as with MoS2 containing surface point defects. The potential of MoS2 as a platform for drug delivery, such as tegafur and lamivudine, is assessed. An exhaustive search for tegafur and lamivudine conformers is performed using the MP2/aug-cc-pVDZ method and four tegafur and sixteen lamivudine conformers are found. Calculations of MoS2 complexes with lower energy conformers of the studied molecules are performed using the DFT/M06-2X method. We demonstrate the possibility of formation of a wide variety of complexes. Complexes with a pristine surface are stabilized only by stacking interactions and have relatively low absolute values of the interaction energies. Accounting for the aqueous environment significantly weakens the stacking interaction to approximately –2 kcal/mol. For complexes stabilized by coordination bonds, the interaction energies are in the range from –90 to –40 kcal/mol. It is sufficient for binding tegafur and lamivudine molecules to MoS2, even taking into account the weakening of the interaction in water to approximately –20 kcal/mol. Analysis of the vibrational spectra of the tegafur and lamivudine complexes with MoS2 allows us to identify spectral markers indicating the formation of the complexes.
Piddubnyi et al. (Thu,) studied this question.