The interaction of liquid water with hydrophobic surfaces is ubiquitous in life and technology. Yet, the molecular structure of interfacial liquid water on these surfaces is not known. By using a 3D atomic force microscope, we characterize with angstrom resolution the structure of interfacial liquid water on hydrophobic and hydrophilic silica surfaces. The combination of 3D AFM images and molecular dynamics simulations reveals that next to a hydrophobic silica surface, there is a 1.2 nm region characterized by a very low density of water. In contrast, the 3D AFM images obtained of a hydrophilic silica surface reveal the presence of hydration layers next to the surface. The gap observed on hydrophobic silica surfaces is filled with two-to-three layers of straight-chain alkanes. We developed a 2D Ising model that explains the formation of a continuous hydrocarbon layer on hydrophobic silica surfaces.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11256893 | PMC |
| http://dx.doi.org/10.1021/acsnano.4c05689 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Hybrid Bilayer Interfaces within Reversed-Phase Chromatographic Silica Formed by Self-Assembly of Long-Chain Primary Alcohols.
Langmuir
January 2025
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States.
Modification of silica interfaces by covalent attachment of functional ligands is a primary means of controlling the interfacial chemistry of porous silicas used in separations, environmental cleanup, and biosensing. Recently, modification of hydrophobic, -alkyl-silane-functionalized interfaces has been achieved through self-assembly of zwitterionic phospholipids or mixed-charged surfactants to form "hybrid bilayers", producing interfaces that mimic lipid-bilayer partitioning and provide shape-selective partitioning of aromatic hydrocarbons. Charged headgroups, however, introduce electrostatic interactions that strongly influence the retention of ionizable solutes and require careful control over pH and ionic strength in the solution phase.
View Article and Find Full Text PDFThe impact of glidants on the rheological properties of active pharmaceutical ingredients: A study of conventional and alternative flow enhancers.
Int J Pharm
January 2025
Laboratory of Pharmaceutical Technology, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, B-9000 Ghent, Belgium.
Nowadays, most of the newly developed active pharmaceutical ingredients (APIs) consist of cohesive particles with a mean particle size of <100μm, a wide particle size distribution (PSD) and a tendency to agglomerate, therefore they are difficult to handle in continuous manufacturing (CM) lines. The current paper focuses on the impact of various glidants on the bulk properties of difficult-to-handle APIs. Three challenging powders were included: two extremely cohesive APIs (acetaminophen micronized (APAPμ) and metoprolol tartrate (MPT)) which previously have shown processing issues during different stages of the continuous direct compression (CDC)-line and a spray dried placebo (SD) powder containing hydroxypropylmethyl cellulose (HPMC), known for its sub-optimal flow with a high specific surface area (SSA) and low density.
View Article and Find Full Text PDFEngineering silica nanocoated whole-cell asymmetric biocatalyst for efficient preparation of a key chiral intermediate of (S)-Rivastigmine.
J Biotechnol
January 2025
Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China. Electronic address:
In our previous study, the whole cells containing an aldo-keto reductase (yhdN) and glucose dehydrogenase (GDH) were constructed and applied in a stereoselective carbonyl reduction reaction to prepare (S)-NEMCA-HEPE, being a key chiral intermediate of (S)-Rivastigmine which is widely prescribed for the treatment of Alzheimer's disease. Although the conversion and enantiomeric excess (e.e.
View Article and Find Full Text PDFSelf-Healing Superhydrophobic Coatings with Multiphase Repellence Property.
ACS Appl Mater Interfaces
January 2025
Centre for Advanced Laser Manufacturing (CALM), School of Mechanical Engineering, Shandong University of Technology, Zibo 255000, P. R. China.
Developing versatile, scalable, and durable coatings that repel various matters in different service environments is of great importance for engineered materials applications but remains highly challenging. Here, the mesoporous silica microspheres (HMS) fabricated by the hard template method were utilized as micro-nanocontainers to encapsulate the hydrophobic agent of perfluorooctyltriethoxysilane (F13) and the corrosion inhibitor of benzotriazole (BTA), forming the functional microsphere of F-HMS(BTA). Moreover, the synthesized organosilane-modified silica sol adhesive (SMP) and F-HMS(BTA) were further employed as the binder and functional filler to construct a superhydrophobic self-healing coating of SMP@F-HMS(BTA) on various engineering metals through scalable spraying.
View Article and Find Full Text PDFHierarchical Biogenic-Based Thermal Insulation Foam.
ACS Nano
January 2025
Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States.
Biogenic-based foam, renowned for its sustainable and eco-friendly properties, is emerging as a promising thermal insulating material with the potential to significantly enhance energy efficiency and sustainability in building applications. However, its relatively high thermal conductivity, large-pore configurations, and energy-intensive manufacturing processes hinder its widespread use. Here, we report on the scalable, one-pot synthesis of biogenic foams achieved by integrating recycled paper pulp and in situ nanoporous silica formation, resulting in a hierarchical structure comprising both micropores and nanopores.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!