Ionic surfactants are known to build up higher interfacial pressures at oil/water interfaces than at air/water interfaces for the same surfactant bulk concentration. Here, we systematically investigate this effect through atomistic molecular dynamics (MD) simulations of surfactant-loaded air/water and oil/water interfaces. Two prototypical ionic surfactants, CTAB and sodium dodecyl sulfate (SDS), are studied and found to give consistent results, which are also robust with respect to variations in the simulation force field. The simulations reproduce the experimental interfacial pressure data on a semiquantitative level and reveal that the influence of oil on the surfactants' in-plane distribution is a major contribution to the observed effect, albeit insufficient to be the sole reason. The simulations are further analyzed with regard to surfactant/oil cooperative/competitive effects that have been invoked recently as an explanation. However, the interfacial orientation of oil molecules, a presumable indicator for such behavior, is found to display changes only for high levels of surfactant coverage.
In alkali/surfactant/polymer (ASP) flooding systems, alkalis react with clay minerals such as Illite, montmorillonite, and kaolinite, leading to reservoir damage and impacting oil recovery rates. Therefore, studying the dissolution effects of strong alkalis on clay minerals is crucial for improving oil recovery. This study uses Illite as a representative clay mineral and employs the ReaxFF reactive force field and molecular dynamics simulations to model its dissolution in NaOH solution.
Department of Biomedicine, Health & Life Convergence Sciences, BK21 Four, Biomedical and Healthcare Research Institute, Mokpo National University, Jeonnam 58554, Republic of Korea; College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Jeonnam 58554, Republic of Korea. Electronic address:
Type 2 diabetes is a chronic disease characterized by insulin resistance and often worsened by obesity. Effective management involves the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) to assist with glycemic control and weight management. However, these drugs must be administered subcutaneously due to their low oral bioavailability.
Vascular malformations are common vascular lesions in infants and seriously affect their health and quality of life. Vascular sclerotherapy is an effective treatment for vascular malformations. However, current sclerosants have difficulty achieving both high efficiency and low toxicity, and their dosing forms make it difficult to achieve long-term retention in the affected blood vessels.
Natural deep eutectic solvents (NADES) represent a significant advance in green chemistry, offering an eco-friendly alternative to conventional organic solvents for applications in extraction, reaction media, and formulations. This study explores the application of NADES in essential oil formulations, using lavender essential oil (LEO) to investigate the solubilization and release of volatile organic compounds (VOCs). Two distinct NADES formulations were evaluated: hydrophilic NADES combined with surfactants, and hydrophobic NADES.
This study focuses on a novel lipase from Bacillus licheniformis IBRL-CHS2. The lipase gene was cloned into the pGEM-T Easy vector, and its sequences were registered in GenBank (KU984433 and AOT80658). It was identified as a member of the bacterial lipase subfamily 1.
