Controlling Liquid Crystal Configuration and Phase Using Multiple Molecular Triggers.

Liquid crystals are able to transform a local molecular interaction into a macroscopic change of state, making them a valuable "smart" material. Here, we investigate a novel polymeric amphiphile as a candidate for molecular triggering of liquid crystal droplets in aqueous background. Using microscopy equipped with crossed polarizers and optical tweezers, we find that the monomeric amphiphile is able to trigger both a fast phase change and then a subsequent transition from nematic to isotropic.

Toward Chemotactic Supramolecular Nanoparticles: From Autonomous Surface Motion Following Specific Chemical Gradients to Multivalency-Controlled Disassembly.

Nature designs chemotactic supramolecular structures that can selectively bind specific groups present on surfaces, autonomously scan them moving along density gradients, and react once a critical concentration is encountered. Since such properties are key in many biological functions, these also offer inspirations for designing artificial systems capable of similar bioinspired autonomous behaviors. One approach is to use soft molecular units that self-assemble in an aqueous solution generating nanoparticles (NPs) that display specific chemical groups on their surface, enabling multivalent interactions with complementarily functionalized surfaces.

Core Hydrophobicity of Supramolecular Nanoparticles Induces NLRP3 Inflammasome Activation.

Designer nanomaterials capable of delivering immunomodulators to specific immune cells have been extensively studied. However, emerging evidence suggests that several of these nanomaterials can nonspecifically activate NLRP3 inflammasomes, an intracellular multiprotein complex controlling various immune cell functions, leading to undesirable effects. To understand what nanoparticle attributes activate inflammasomes, we designed a multiparametric polymer supramolecular nanoparticle system to modulate various surface and core nanoparticle-associated molecular patterns (NAMPs), one at a time.

Polymer with Competing Depolymerization Pathways: Chain Unzipping versus Chain Scission.

Interest in triggered depolymerization is growing, driven by needs in sustainable plastics, self-healing materials, controlled release, and sensory amplification. For many triggered depolymerization reactions, the rate-limiting step does not directly involve the stimulus, and therefore, depolymerization kinetics exhibit only weak or no correlation to the concentration and reactivity of the stimulus. However, for many applications, a direct relationship between the stimulus and the depolymerization kinetics is desired.

Optical "Blinking" Triggered by Collisions of Single Supramolecular Assemblies of Amphiphilic Molecules with Interfaces of Liquid Crystals.

We report that incubation of aqueous dispersions of supramolecular assemblies formed by synthetic alkyl triazole-based amphiphiles against interfaces of thermotropic liquid crystals (LCs; 4-cyano-4'-pentylbiphenyl) triggers spatially localized (micrometer-scale) and transient (subsecond) flashes of light to be transmitted through the LC. Analysis of the spatiotemporal response of the LC supports our proposal that each optical "blinking" event results from collision of a single supramolecular assembly with the LC interface. Particle tracking at the LC interface confirmed that collision and subsequent spreading of amphiphiles at the interface generates a surface pressure-driven interfacial flow (Marangoni flow) that causes transient reorientation of LC and generation of a bright optical flash between crossed polarizers.