Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Surface Active Agents

Surface Active Agents

Surfactants, named for their behavior at interfaces, positively adsorb at the interfaces of two phases, reducing interfacial tension. Their versatility as emulsifiers, detergents, and foaming agents stems from this ability. Surfactants, often termed amphiphiles, share the property of amphipathy, with molecules having both hydrophilic and hydrophobic portions. The hydrophilic part is called the head, and the hydrophobic part, including an elongated alkyl substituent, forms the tail.Surfactants...

Micelles

Micelles

Micelle formation is an intricate process that hinges on the properties of amphiphilic or amphipathic molecules and the conditions of the system in which they are found. Amphiphilic molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, play a critical role in this process.In aqueous environments, these molecules arrange themselves such that their hydrophilic heads are turned towards the water phase, while their hydrophobic tails are oriented away...

Colloids

Colloids

Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...

Surface Tension and Surface Energy

Surface Tension and Surface Energy

When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...

Colloidal precipitates

Colloidal precipitates

The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...

The Electrical Double Layer

The Electrical Double Layer

In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Preoperative Nutritional Risk Defines Treatment Tolerance and Guides Adjuvant Immunotherapy in Resectable Esophageal Squamous Cell Carcinoma.

Annals of surgical oncology·2026

Same author

Lymphovascular and perineural invasion guides adjuvant therapy after neoadjuvant chemoimmunotherapy in esophageal squamous cell carcinoma.

The oncologist·2026

Same author

Refining post-neoadjuvant risk stratification in ESCC with lymph node regression grade.

Frontiers in oncology·2026

Same author

Angiotensin inhibitors during neoadjuvant chemotherapy improve esophageal squamous cell carcinoma outcomes.

Therapeutic advances in medical oncology·2026

Same author

Ferroptosis and Wnt/β-Catenin Signaling Triggered by Environmentally Relevant Nanoscale Polypropylene Plastics in Human Intestinal Models.

ACS environmental Au·2026

Same author

Reply to "Enhancing Postoperative Decision-Making in Esophageal Cancer: Clinical Perspectives and Future Research Needs".

Cancer medicine·2026

Search research articles

Related Experiment Video

Updated: Jul 14, 2026

Microtensiometer for Confocal Microscopy Visualization of Dynamic Interfaces

Microtensiometer for Confocal Microscopy Visualization of Dynamic Interfaces

Published on: September 9, 2022

Electric-field-driven surface aggregation of a model zwitterionic surfactant.

Shimin Xu¹, Maohui Chen, Ewa Cholewa

¹Department of Chemistry, University of Guelph, Guelph, Ontario, Canada.

Langmuir : the ACS Journal of Surfaces and Colloids

|May 26, 2007

Summary

Electric fields precisely control zwitterionic surfactant aggregation on gold surfaces. The metal

More Related Videos

Multiscale Structures Aggregated by Imprinted Nanofibers for Functional Surfaces

Multiscale Structures Aggregated by Imprinted Nanofibers for Functional Surfaces

Published on: September 11, 2018

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops

Published on: July 11, 2025

Related Experiment Videos

Last Updated: Jul 14, 2026

Microtensiometer for Confocal Microscopy Visualization of Dynamic Interfaces

Microtensiometer for Confocal Microscopy Visualization of Dynamic Interfaces

Published on: September 9, 2022

Multiscale Structures Aggregated by Imprinted Nanofibers for Functional Surfaces

Multiscale Structures Aggregated by Imprinted Nanofibers for Functional Surfaces

Published on: September 11, 2018

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops

Tuning the Contractility and Deformation Modes of Active Actin-Based Assemblies In Vitro: From Two-Dimensional Active Networks to Liquid Crystal Drops

Published on: July 11, 2025

Area of Science:

Electrochemistry
Surface Science
Materials Science

Background:

Zwitterionic surfactants are crucial in various applications.
Understanding their surface behavior is key for material design.
Electric field effects on adsorbed molecules are complex.

Purpose of the Study:

To investigate the electric-field-controlled surface aggregation of N-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (DDAPS).
To elucidate the relationship between metal surface charge and surfactant film structure.
To visualize field-driven aggregation using advanced microscopy.

Main Methods:

Combined electrochemical measurements with Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM).
Studied DDAPS at a Au(111) electrode surface.
Varied metal surface charge density (sigmaM) and DDAPS concentration relative to the critical micelle concentration (CMC).

Main Results:

Monolayer adsorption and aggregation occurred below the CMC, with film structure dictated by sigmaM.
High negative sigmaM yielded disordered films; high positive sigmaM resulted in planar films with blisters.
Intermediate charge densities showed hemicylindrical aggregates; above CMC, adsorbed micelles fused.
AFM and STM provided direct visualization of field-driven aggregation.

Conclusions:

The electric field strongly influences the orientation and aggregation of zwitterionic surfactants on metal surfaces.
Surface charge density is a critical parameter controlling the nanostructure of surfactant films.
This work offers insights into field-effect phenomena in surfactant systems.