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The capability of ordinary surfactants in solubilizing hydrophobic compounds can come to a limit, if the extension of a contaminant is too large. An attractive goal is the development of surfactants which can actively reduce the size of dirt. Because strong Lewis acids are known to catalyze both bond formation and cleavage, an integration into the surfactant's molecular framework is tempting. End-group functionalized hepta-dentate ligands, which coordinate to metal ions preventing deactivation by hydrolysis over a broad range of pH values while maintaining strong Lewis-acidity, are herein presented. After proof of amphiphilicity and surfactant characteristics, catalytic properties are investigated for different reactions including the cleavage of proteins. The compounds perform better than benchmark catalysts concerning the attack of unreactive amide bonds. A study with two Sc3+ species as the active site, one non-amphiphilic, the other one being surface-active, underlines the positive effect of surfactant properties for boosting catalytic efficiency. [ABSTRACT FROM AUTHOR]

Amphiphiles alter the energy of surfaces, but the extent of this feature is typically constant. Smart systems with amphiphilicity as a function of an external, physical trigger are desirable. As a trigger, the exposure to a magnetic field, in particular, is attractive because it is not shielded in water. Amphiphiles like surfactants are well known, but the magnetic response of molecules is typically weak. Vice‐versa, magnetic particles with strong response to magnetic triggers are fully established in nanoscience, but they are not amphiphilic. In this work colloids with Janus architecture and ultra‐small dimensions (25 nm) have been prepared by spatial control over the thiol‐yne click modification of organosilica‐magnetite core–shell nanoparticles. The amphiphilic properties of these anisotropically modified particles are proven. Finally, a pronounced and reversible change in interfacial stabilization results from the application of a weak (<1 T) magnetic field. [ABSTRACT FROM AUTHOR]

Surfactants are ubiquitous in cellular membranes, detergents or as emulsification agents. Due to their amphiphilic properties, they cannot only mediate between two domains of very different solvent compatibility like water and organic but also show fascinating self‐assembly features resulting in micelles, vesicles, or lyotropic liquid crystals. The current review article highlights some approaches towards the next generation surfactants, for example, those with catalytically active heads. Furthermore, it is shown that amphiphilic properties can be obtained beyond the classical hydrophobic–hydrophilic interplay, for instance with surfactants containing one molecular block with a special shape. Whereas, classical surfactants are static, researchers have become more interested in species that are able to change their properties depending on external triggers. The article discusses examples for surfactants sensitive to chemical (e.g. pH value) or physical triggers (temperature, electric and magnetic fields). More than soap: Surfactants with additional functionalities cross the current frontiers in self‐assembly research. The article highlights representative cases for catalytic surfactants and stimuli‐responsive amphiphiles. [ABSTRACT FROM AUTHOR]

Amphiphiles and surfactants are indispensable compounds in industry, scientific research and everyday life, such as emulsification agents, detergents, etc. The vast majority of currently used amiphiphiles are organic in nature, and are composed of two molecular parts joined together, one hydrophilic and one hydrophobic. The current article highlights some of the recent developments in the emerging field of hybrid amphiphiles, focusing on systems with at least one inorganic constituent. Different classes of amphiphiles can be defined, depending on if the inorganic entity is molecular or has particle character, and depending on the strength of interaction between the inorganic and organic phase. It is seen that in addition to typical amphiphilic properties, most importantly the formation of self-assembled structures like micelles or lyotropic liquid crystals, the hybrid amphiphiles exhibit additional, functional features like special magnetic or catalytic properties. Ultimately, systemic features can be observed, leading to the emergence of new properties which none of the constituents of hybrid amphiphile could have on its own. [ABSTRACT FROM AUTHOR]

Surfactants are molecules of enormous scientific and technological importance, which are widely used as detergents, emulsifiers, and for the preparation of diverse nanostructures. Their fascinating ability to form self-organized structures, such as micelles or liquid crystals, originate from their amphiphilic architecture-a polar head group linked to a hydrophobic chain. While almost all known surfactants are organic, a new family of surfactants is now emerging, which combines amphiphilic properties with the advanced functionality of transition-metal building blocks, for example, redox or catalytic activity and magnetism. These hybrid surfactants exhibit novel self-organization features because of the unique size and electronic properties of the metal-containing entities. [ABSTRACT FROM AUTHOR]

Magnetic moustaches: Inorganic surfactants (I‐SURFs) with head groups containing Dy3+ undergo a hierarchical self‐organization cascade controlled by magnetic interactions. The resulting aggregates are shaped like dumbbells with frayed, moustache‐like ends. [ABSTRACT FROM AUTHOR]

Surfactants are functional molecules, which are used to stabilize interfaces of all kind, for example, in foams. They are produced in large amounts by the chemical industry and represent an inherent part of everyone′s daily routine. Next‐generation surfactants contain at least one additional feature, for example catalytic activity or special redox properties. Another class offers smart properties like thermoresponsivity. Ultimately, the surfactant′s head could reach a high degree of multifunctionality, "comparable" to a swiss army knife. For a comprehensive discussion see the Minireview by S. Polarz et al. on page 18842 ff. [ABSTRACT FROM AUTHOR]