Exploring the mechanisms of diazinon adsorption onto alpha and beta cyclodextrins through molecular dynamics simulations: Insights into environmentally friendly pesticide remediation

Abstract

This study investigated the adsorption of Diazinon on α and β-Cyclodextrins (CDs) through Molecular Dynamics Simulations. The entrance point variation in diazinon adsorption is analyzed, revealing distinct preferences for entry into α and β-CDs. The center of mass distance of diazinon and CDs is investigated, highlighting the dynamic behavior within β-CD. Interaction energies between diazinon, CD, and water are explored, emphasizing the significance of van der Waals interactions in diazinon adsorption. Hydrogen bonding analysis reveals preferential adsorption of diazinon on α-CD, attributed to the number and arrangement of hydrogen bonds. Free energy calculations using the Bennett acceptance ratio method indicate a stronger affinity of diazinon for α-CD, supported by molecular electrostatic potential maps. The study also examines the hydration capacity and water molecules' distribution, indicating differences between α and β-CD. Radial distribution function analysis (RDF) illustrates the adsorption process, emphasizing water molecule expulsion upon diazinon entry. Structural stability is assessed through root mean squared deviation, indicating equilibrium attainment. Gibbs free energy calculations suggest stronger hydrophobic interactions in the α-CD cavity. This comprehensive analysis contributes valuable insights into the MD of diazinon-CDs interactions, shedding light on their adsorption mechanisms and potential applications in wastewater treatment.