Molecular interactions of praziquantel drug with nanosurfaces of sepiolite and montmorillonite

Praziquantel drug is nowadays in continuo study to overcome adverse biopharmaceutical properties as drug of first choice for the treatment of the human schistosomiasis. Meanwhile, sepiolite and montmorillonite have been studied experimentally as low-cost nanocarrier to design new praziquantel delivery systems. In this work, the interactions between the drug and clay minerals surfaces are studied at molecular level by computational methods. The optimization of the adsorption of praziquantel in sepiolite nanochannels and in the montmorillonite interlayer space has been studied by using force fields based on empirical interatomic potentials and at quantum mechanical level. The results showed the main interactions between the drug and both clay minerals surfaces at the confined spaces of these minerals, and favorable adsorption energies of the praziquantel-clays complexes were obtained. Therefore, theoretical calculations allow knowing how the drug is adsorbed in the clays and in the case of the montmorillonite how many molecules of the drug are adsorbed in the interlayer space of the mineral according to the experimental data.