Journal of molecular graphics & modelling最新文献

Lidocaine (LDC) is one of the most important local anaesthesia compounds (LAs), designated to treat acute and chronic pain, especially in clinical applications. In the purpose to improve its lower solubility and bioavailability, numerous researches have been conducted to study the exact mode of association between the LDC molecule and cyclodextrins as drug carriers. Although, the reported structural details on LDC/β-CD and LDC/HP-β-CD inclusion complexes remain largely unexplored. The LDC molecule presents different spatial arrangements inside the hydrophobic cavities of the above-mentioned hosts; either the phenyl moiety or the diethylamino part is totally inserted. Hence, in the present work, we attempt to deepen our understanding about conformational preferences on the binding modes of LDC by investigating the quantum mechanical approach results. The PM3 method combined with the pure corrected functional B97D3 revealed the tendency of LDC to enter its diethylamino inside the host, leaving the rest of molecule externally, and consequently form an inclusion complex with HP-β-CD more stable than with the native β-CD by approximately 12 kcal mol^-1. The probability of partial insertion of LDC is further ascertained by MD simulations investigation running for 500 ns. The trajectory analysis of MD process showed that the diethyl amino fragment is accommodated inside the HP-β-CD's cavity for a significant period (82 % of the simulation time), while it is estimated to be 78 % in the case of LDC/β-CD complex. Moreover, the wave function analysis, based on QTAIM, Reduced Density Gradient (RDG) and 2D Fingerprint, illustrated NCIs interactions and sustained the contribution of numerous van der Waals forces and weaker H-bonds interactions in the stability of studied ICs.

The versatile properties of graphene-based polymers have captured substantial interest in recent years, making them a topic of significant research focus. This review paper aims to provide an in-depth analysis of the reported mechanical properties of graphene polymer nanocomposites, a highly promising class of materials for diverse industrial applications. Within this review, we emphasize the role of interactions between graphene and the polymer matrix in achieving uniform dispersion to prevent agglomeration and mitigate adverse effects on mechanical properties. Furthermore, we focus on functionalization as the main method of enhancing graphene physicochemical properties, highlighting its capacity to enhance homogeneous dispersion and significantly improve mechanical properties. These enhancements are contingent on factors such as the type and quantity of functionalization agents and the chosen technique. Additionally, we comprehensively examine recent experimental and theoretical research pertaining to the mechanical properties of graphene/polymer nanocomposites. Our analysis contains two primary polymer categories, namely thermoset and thermoplastic matrices, while also considering graphene loading type and volume fraction, as well as the influence of functionalization agents. This review uniquely addresses the existing gap in a comparative analysis between thermoset and thermoplastic matrices, offering insights into how different loading and functionalization methods influence mechanical properties. Moreover, we emphasize the need for further research in optimizing functionalization techniques and understanding the long-term stability of these composites, an area underexplored in current literature. This work stands out by highlighting future directions for refining synthesis techniques and expanding applications of graphene/polymer nanocomposites across industries such as aerospace, automotive, and electronics. Future endeavors may focus on addressing the challenges, refining synthesis techniques, and exploring novel applications, thereby contributing to the continued growth and evolution of graphene/polymer nanocomposites in the field of materials science.

Because of its superior mechanical and electrical insulation qualities, paramamid insulating paper is frequently used in the electrical industry. However, a significant barrier preventing it from taking a more prominent role is its low heat conductivity. This research modifies aramid by doping it with carbon nanotubes and alumina to balance its insulating qualities and increase its thermal conductivity. Materials Studio uses molecular dynamics (MD) computations to examine the thermodynamic parameters of the composite system, such as modulus, glass transition temperature, and thermal conductivity. the system's cohesive energy density, free volume fraction, mean square displacement, and other structural characteristics. The relative dielectric constant is used to calculate the insulating characteristics. The Density Functional Theory (DFT) is then used to calculate the fluctuation of the electrostatic potential with Mulliken charge on the electrical properties. According to the findings, a single doped carbon nanotube significantly raises its mechanical and thermal conductivity while completely destroying its insulation. While single alumina doping increases the insulating properties of the system and yields improved structural parameters and tighter intermolecular bonding, it has minimally positive effects on its thermal conductivity. When mixed doping is used, the system's thermodynamics will be significantly enhanced without compromising its insulating qualities.

Acetylcholinesterase (AChE) is one of the most successful targets for the treatment of Alzheimer's disease (AD). Inhibition of AChE can result in preventing AD. In this context, the machine-learning (ML) model, molecular docking, and molecular dynamics calculations were employed to characterize the potential inhibitors for AChE from MedChemExpress (MCE) database. The trained ML model was initially employed for estimating the inhibitory of MCE compounds. Atomistic simulations including molecular docking and molecular dynamics simulations were then used to confirm ML outcomes. In particular, the physical insights into the ligand binding to AChE were clarified over the calculations. Two compounds, PubChem ID of 130467298 and 132020434, were indicated that they can inhibit AChE.