Magnetic liquid marbles capable of hosting both aqueous and organic fluids may serve as new miniature chemical reactors. Chemical reactions can occur either within a single liquid marble or between two magnetic liquid marbles (as illustrated). The liquid marbles can also interact with external devices simply by opening and closing the powdery shell under a magnetic field.

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Existing coating systems for preparing superamphiphobic surfaces are predominantly confined into small-scale uses due to the heavy use of organic solvents. Waterborne coating treatment is highly desirable for the high safety, low cost, and non-environmental impact, but remains difficult to develop due to the problems in forming durable, homogeneous coating from an aqueous dispersion of amphiphobic substances. In this study, we have proved that lyophobic nanoparticles, fluorinated alkyl silane (FAS), and fluorocarbon surfactant can form a stable dispersion in water, suitable for preparing durable superamphiphobic surfaces on various solid This article is protected by copyright. All rights reserved. 2 substrates. A series of substrates including fabrics, sponge, wood, glass, and metal, after being coated with this ternary coating system show superamphiphobicity with low contact angle hysteresis. The coating is durable enough against physical abrasion, repeated washing, boiling in water, and strong acid/base attacks. Benefiting from FAS, the coating also has a self-healing ability against both physical and chemical damages. The unexpected stability of the ternary dispersion is a result of the synergistic interaction of the three ingredients. Results from this study may promote the wide development of safe, and cost-efficient superamphiphobic techniques for diverse applications.Received: ((will be filled in by the editorial staff))Revised: ((will be filled in by the editorial staff)) Published online: ((will be filled in by the editorial staff))

Superhydrophilic and superoleophobic materials are very attractive for efficient and cost-effective oil-water separation, but also very challenging to prepare. Reported herein is a new superamphiphobic coating that turns superhydrophilic and superoleophobic upon ammonia exposure. The coating is prepared from a mixture of silica nanoparticles and heptadecafluorononanoic acid-modified TiO2 sol by a facile dip-coating method. Commonly used materials, including polyester fabric and polyurethane sponge, modified with this coating show unusual capabilities for controllable filtration of an oil-water mixture and selective removal of water from bulk oil. We anticipate that this novel coating may lead to the development of advanced oil-water separation techniques.

Liquid marbles exhibit great potential for use as miniature labs for small‐scale laboratory operations, such as experiment and measurement. While important progress has been made recently in exploring their applications as microreactions, “on‐line” measurement of the components inside the liquid still remains a challenge. Herein, it is demonstrated that “on‐line” detection can be realized on magnetic liquid marbles by taking advantage of their unique magnetic opening feature. By partially opening the particle shell, electrochemical measurement is carried out with a miniaturized three‐electrode probe and the application of this technique for quantitative measurement of dopamine is demonstrated. Fully opened magnetic liquid marble makes it feasible to detect the optical absorbance of the liquid in a transmission mode. With this optical method, a glucose assay is demonstrated. Moreover, when magnetic particle shell contains low melting point material, e.g., wax, the liquid marble shows a unique encapsulation ability to form a rigid shell after heating, which facilitates the storage of the non‐volatile ingredients. These unique features, together with the versatile use as microreactors, enable magnetic liquid marbles to function as a miniature lab (or called “lab in a droplet”), which may find applications in clinical diagnostics, biotechnology, chemical synthesis, and analytical chemistry.

Magnetic liquid marbles, an encapsulation of liquid droplet with hydrophobic magnetic particles, show remarkable responsiveness to external magnetic force and great potential to be used as a discrete droplet microfluidic system. In this study, we presented the manipulation of a magnetic liquid marble under an external magnetic field and calculated the maximum frictional force, the magnetic force required for actuating the liquid marbles and the effective surface tension of the magnetic liquid marble, as well as the threshold volume for the transition from quasispherical to puddle-like shape. By taking advantage of the unique feature of being opened and closed reversibly, we have proven the encapsulated droplets can be detected optically with a reflection-mode probe. Combining the open-close and optical detection also enables to probe chemical reactions taking place within liquid marbles. These remarkable features offer a simple yet powerful alternative to conventional discrete microfluidic systems and may have wide applications in biomedical and drug discovery.

Directional fluid motion driven by the surface property of solid substrate is highly desirable for manipulating microfluidic liquid and collecting water from humid air. Studies on such liquid motion have been confined to dense material surfaces such as flat panels and single filaments. Recently, directional fluid transport through the thickness of thin porous materials has been reported by several research groups. Their studies not only attract fundamental, experimental and theoretical interest but also open novel application opportunities. This review article summarizes research progress in directional fluid transport across thin porous materials. It focuses on the materials preparation, basic properties associated with directional fluid transport in thin porous media, and their application development. The porous substrates, type of transporting fluids, structure-property attributes, and possible directional fluid transport mechanism are discussed. A perspective for future development in this field is proposed.

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