ABSTRACT
Owing to the fact that the use of 2,2-dichlorovinyldimethylphosphate (DDVP) as an agrochemical has become a matter of concern due to its persistence and potential harm to the environment and human health. Detecting and addressing DDVP contamination is crucial to protect human health and mitigate ecological impacts. Hence, this study focuses on harnessing the properties of fullerene (C60) carbon materials, known for their biological activities and high importance, to develop an efficient sensor for DDVP. Additionally, the sensor's performance is enhanced by doping it with gallium (Ga) and indium (In) metals to investigate the sensing and trapping capabilities of DDVP molecules. The detection of DDVP is carefully examined using first-principles density functional theory (DFT) at the Def2svp/B3LYP-GD3(BJ) level of theory, specifically analyzing the adsorption of DDVP at the chlorine (Cl) and oxygen (O) sites. The adsorption energies at the Cl site were determined as - 57.894 kJ/mol, - 78.107 kJ/mol, and - 99.901 kJ/mol for Cl_DDVP@C60, Cl_DDVP@Ga@C60, and Cl_DDVP@In@C60 interactions, respectively. At the O site, the adsorption energies were found to be - 54.400 kJ/mol, - 114.060 kJ/mol, and - 114.056 kJ/mol for O_DDVP@C60, O_DDVP@Ga@C60, and O_DDVP@In@C60, respectively. The adsorption energy analysis highlights the chemisorption strength between the surfaces and the DDVP molecule at the Cl and O sites of adsorption, indicating that the O adsorption site exhibits higher adsorption energy, which is more favorable according to the thermodynamics analysis. Thermodynamic parameters (∆H and ∆G) obtained from this adsorption site suggest considerable stability and indicate a spontaneous reaction in the order O_DDVP@Ga@C60 > O_DDVP@In@C60 > O_DDVP@C60. These findings demonstrate that the metal-decorated surfaces adsorbed on the oxygen (O) site of the biomolecule offer high sensitivity for detecting the organophosphate molecule DDVP.
ABSTRACT
Nanostructures such as nanosheets, nanotubes, nanocages, and fullerenes have been extensively studied as potential candidates in various fields since the advancement of nanoscience. Herein, the interaction between biguanides (BGN) and metformin (MET) on the modified covalent organic framework (COF), COF-B, and COF-Al was investigated using density functional theory at the ωB97XD/6-311+G (d, p) level of computation to explore a new drug delivery system. The electronic properties evaluation reveals that the studied surfaces are suited for the delivery of both drug molecules. The calculated adsorption energies and basis set superposition errors (BSSE) ranged between -21.20 and -65.86 kJ/mol. The negative values obtained are an indication of excellent interaction between the drug molecules and the COF surfaces. Moreover, BGN is better adsorbed on COF-B with Eads of -65.86 kJ/mol, while MET is better adsorbed on COF-Al with Eads = -47.30 kJ/mol. The analysis of the quantum theory of atom in molecules (QTAIM) explained the nature and strength of intermolecular interaction existing between the drug molecules BGN and MET with the adsorbing surfaces. The analysis of noncovalent interaction (NCI) shows a weak hydrogen-bond interaction. Other properties such as quantum chemical descriptors and natural bond orbital (NBO) analysis also agree with the potential of COF surfaces as drug delivery systems. The electron localization function (ELF) is discussed, and it confirms the transitions occurring in the NBO analysis of the complexes. In conclusion, COF-B and COF-Al are suitable candidates for the effective delivery of BGN and MET.
