Mechanistic understanding of nanoparticle interactions to achieve highly-ordered arrays through self-assembly for sensitive surface-enhanced Raman scattering detection of trace thiram.

Over the last few decades, there is increasing worldwide concern over human health risks associated with extensive use of pesticides in agriculture. Developing excellent SERS substrate materials to achieve highly sensitive detection of pesticide residues in the food is very necessary owing to their serious threat to human health through food chains. Self-assembled metallic nanoparticles have been demonstrated to be excellent SERS substrate materials.

Compositions analysis and insecticidal activity of Aconitum polycarpum Chang ex W.T.Wang petroleum ether fractions and essential oils.

Ethnopharmacological Relevance: The Aconitum genus plants as a natural pesticide for insecticide and rodent control has been recorded in Chinese folk. However, the insecticide effect, mechanism, and active composition of Aconitum polycarpum Chang ex W.T.

Cell-Mimic Directional Cargo Transportation in a Visible-Light-Activated Colloidal Motor/Lipid Tube System.

Active tether and transportation of cargoes on cytoskeletal highway enabled by molecular motors is key for accurate delivery of vesicles and organelles in the complex intracellular environment. Here, a hybrid system composed of colloidal motors and self-assembled lipid tubes is designed to mimic the subcellular traffic system in living cells. The colloidal motors, composed of gold-coated hematite, display light-activated self-propulsion tunable by the light intensity and the concentration of hydrogen peroxide fuel.

High salinity effects on the depletion attraction in colloid-polymer mixtures.

Hypothesis: Depletion attraction induced by polymers can be employed across multiple disciplines. Previous studies implied that besides screening the electrostatic repulsion between colloids, adding salt may also affect the polymers even in a nonpolar solvent. Here, we study the depletion-induced gelation of a colloid-polymer model system, focusing on the salt effects on the depletion attraction.

Estimating the velocity of chemically-driven Janus colloids considering the anisotropic concentration field.

The application of the active colloids is strongly related to their self-propulsion velocity, which is controlled by the generated anisotropic concentration field. We investigated the effect of this anisotropy on velocity induced by numerical treatments and size of Janus colloids. The far-field approximation is effective in estimating the velocity, even though it neglects the shape effect on the anisotropy of the concentration field.

Corrigendum: Self Organization of Binary Colloidal Mixtures via Diffusiohporesis.

[This corrects the article DOI: 10.3389/fchem.2022.

Binary Phases and Crystals Assembled from Active and Passive Colloids.

Classic binary materials, ranging from polymer blends to table salts, contain equilibrium phases or crystals of two interacting components. Here, we report on the construction of binary colloidal materials out of equilibrium by employing active particles and passive particles that dynamically interact and organize. Key to our scheme is the introduction of photoactive microspheres whose activity can be precisely tuned.

Self-Organization of Binary Colloidal Mixtures via Diffusiophoresis.

Catalytic activity of the colloids and chemotactic response to gradients of the chemicals in the solution leads to effective interaction between catalytic colloids. In this paper, we simulate mixtures of active and passive colloids via a Brownian dynamics algorithm. These particles interact via phoretic interactions, which are determined by two independent parameters, surface activity and surface mobility.

Inorganic-Organic Hybrid Copolymeric Colloids as Multicolor Emission, Fuel-Free, UV- and Visible-Light-Actuated Micropumps.

Light-actuated micromachines are of enormous interest due to their ability to harvest light for triggering catalytic reactions to acquire free energy for mechanical work. This work presents an inorganic-organic hybrid copolymeric poly(cyclotriphosphazene-co-barbituric acid) colloid, which displays multiwavelength excited emission and catalytic activities, exploiting the unique structural, chemical, and optical features of inorganic heterocyclic ring hexachlorocyclotriphosphazene and organic co-monomer barbituric acid. Specifically, this work reveals particle-resolved unusual multicolor emission under excitation with the same or different wavelengths of light using fluorescence microscopy.

Magnetic Manipulation and Assembly of Nonmagnetic Colloidal Rods in a Ferrofluid.

We investigated experimentally and theoretically the interactions and assembly of rodlike colloids in a ferrofluid confined at solid/liquid interface by the gravity under external magnetic fields. We first derived analytical expressions for the interaction energy of a single rod with the external magnetic field and the interaction between two rods using classical electromagnetism. The theory well captured the experimentally observed alignment of a single rod along the field direction under an in-plane field and switching between the horizontal and the vertical configurations in an out-of-plane field due to the competition between the magnetic energy and the gravitational energy.

Thermoresponsive Hydrogel Induced by Dual Supramolecular Assemblies and Its Controlled Release Property for Enhanced Anticancer Drug Delivery.

Supramolecular hydrogels based on inclusion complexation between cyclodextrins (CDs) and polymers have attracted much interest because of their potential for biomedical applications. It is also attractive to incorporate stimuli-responsive properties into the system to create "smart" hydrogels. Herein, a poly(-isopropylacrylamide) (PNIPAAm) star polymer with a β-CD core and an adamantyl-terminated poly(ethylene glycol) (Ad-PEG) polymer were synthesized.