Subcellular compartmentalization of cells, a defining characteristic of eukaryotes, is fundamental for the fine tuning of internal processes and the responding to external stimuli. Reproducing and controlling such compartmentalized hierarchical organization, responsiveness, and communication is important toward understanding biological systems and applying them to smart materials. Herein, a cellular signal transduction strategy (triggered release from subcompartments) is leveraged to develop responsive, purely artificial, polymeric multicompartment assemblies. Incorporation of responsive nanoparticles-loaded with enzymatic substrate or ion channels-as subcompartments inside micrometersized polymeric vesicles (polymersomes) allowed to conduct bioinspired signaling cascades. Response of these subcompartments to an externally added stimulus is achieved and studied by using confocal laser scanning micro scopy (CLSM) coupled with in situ fluorescence correlation spectroscopy (FCS). Signal triggered activity of an enzymatic reaction is demonstrated in multicompartments through recombination of compartmentalized substrate and enzyme. In parallel, a two-step signaling cascade is achieved by triggering the recruitment of ion channels from inner subcompartments to the vesicles' membrane, inducing ion permeability, mimicking endosome-mediated insertion of internally stored channels. This design shows remarkable versatility, robustness, and controllability, demonstrating that multicompartment polymer-based assemblies offer an ideal scaffold for the development of complex cell-inspired responsive systems for applications in biosensing, catalysis, and medicine.

Organelles, i.e., internal subcompartments of cells, are fundamental to spatially separate cellular processes, while controlled intercompartment communication is essential for signal transduction. Furthermore, dynamic remodeling of the cytoskeleton provides the mechanical basis for cell shape transformations and mobility. In a quest to develop cell‐like smart synthetic materials, exhibiting functional flexibility, a self‐assembled vesicular multicompartment system, comprised of a polymeric membrane (giant unilamellar vesicle, GUV) enveloping polymeric artificial organelles (vesicles, nanoparticles), is herein presented. Such multicompartment assemblies respond to an external stimulus that is transduced through a precise sequence. Stimuli‐triggered communication between two types of internal artificial organelles induces and localizes an enzymatic reaction and allows ion‐channel mediated release from storage vacuoles. Moreover, cytoskeleton formation in the GUVs' lumen can be triggered by addition of ionophores and ions. An additional level of control is achieved by signal‐triggered ionophore translocation from organelles to the outer membrane, triggering cytoskeleton formation. This system is further used to study the diffusion of various cytoskeletal drugs across the synthetic outer membrane, demonstrating potential applicability, e.g., anticancer drug screening. Such multicompartment assemblies represent a robust system harboring many different functionalities and are a considerable leap in the application of cell logics to reactive and smart synthetic materials.

We present a dynamic ion-atom hybrid trap for studies of cold ion-neutral collisions and reactions with a significantly improved energy resolution compared to previous experiments. Our approach is based on pushing a cloud of laser-cooled Rb atoms through a stationary Coulomb crystal of cold ions using precisely controlled, tunable radiation-pressure forces. We demonstrate the tuning of the atom kinetic energies over an interval ranging from 30 mK up to 350 mK with energy spreads as low as 24 mK inferred from the comparison of experimental time-of-flight measurements with Monte Carlo trajectory simulations. We also demonstrate first applications of our method to the investigation of chemical reactions. Our development opens up perspectives for accurate studies of the energy dependence of the reaction rates, the dynamics and the reaction-product ratios of ion-neutral processes in the cold regime. It also paves the way for the realisation of fully energy-and state-controlled cold-collision experiments.

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Trapped cold molecules represent attractive systems for precision-spectroscopic studies and for investigations of cold collisions and chemical reactions. However, achieving their confinement for sufficiently long timescales remains a challenge. Here, we report the long-term trapping of Stark-decelerated OH radicals in their X 2 Π 3/2 (ν = 0, J = 3/2, M J = 3/2, f) state in a permanent magnetic trap. The trap environment is cryogenically cooled to a temperature of 17 K to suppress black-body-radiation-induced pumping of the molecules out of trappable quantum states and collisions with residual background gas molecules which usually limit the trap lifetime. The cold molecules are thus confined on timescales approaching minutes, an improvement of up to two orders of magnitude compared with room temperature experiments, at translational temperatures of ∼25 mK. The present results pave the way for new experiments using trapped cold molecules in precision spectroscopy, in studies of slow chemical processes at low energies and in the quantum technologies.