Related Experiment Video
Updated: Jun 21, 2026
06:28
Self-Assembly of Hybrid Lipid Membranes Doped with Hydrophobic Organic Molecules at the Water/Air Interface
Published on: May 1, 2020
Triggered self-assembly of simple dynamic covalent surfactants
Christophe B Minkenberg1, Louw Florusse, Rienk Eelkema
1Delft University of Technology, DelftChemTech, Julianalaan 136, 2628 BL Delft, The Netherlands.
Journal of the American Chemical Society
|July 25, 2009
Summary
Researchers created a novel switchable surfactant system that self-assembles into micelles using dynamic covalent bonds. This system allows for controlled on/off aggregation triggered by pH and temperature, showing potential for drug delivery applications.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Chemical Engineering
Background:
- Traditional surfactants exhibit fixed amphiphilic properties.
- Controlling surfactant aggregation is crucial for applications like drug delivery.
- Dynamic covalent chemistry offers responsive molecular interactions.
Purpose of the Study:
- To develop a novel surfactant system with tunable aggregation states.
- To utilize dynamic covalent bonds for stimuli-responsive self-assembly.
- To demonstrate the controlled release capabilities of the switchable surfactant system.
Main Methods:
- Design and synthesis of a prototype surfactant molecule.
- Investigation of self-assembly behavior using pH and temperature stimuli.
- Characterization of micellar aggregate formation and dissociation.
- Evaluation of controlled release using an organic dye model.
Main Results:
- A switchable surfactant system was successfully developed, transitioning between aggregated and nonaggregated states.
- Reversible micellar self-assembly was achieved via pH- and temperature-triggered dynamic covalent bond formation.
- The system demonstrated controlled uptake and release of an organic dye in aqueous media.
- The surfactant's amphiphilic and nonamphiphilic states were modulated by external stimuli.
Conclusions:
- The developed switchable surfactant system offers a novel approach for stimuli-responsive self-assembly.
- Dynamic covalent chemistry provides an effective mechanism for on/off control of micellar aggregation.
- The system shows promise for applications in controlled release and advanced materials design.
Related Concept Videos
01:30Micelles
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...
01:27Surface 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...
03:22Colloids
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...
00:57Cationic Chain-Growth Polymerization: Mechanism
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the generated carbocation,...
00:59Mechanisms of Membrane Domain Formation
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...
01:04Anionic Chain-Growth Polymerization: Mechanism
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael acceptor.