ChemSystemsChem最新文献

Cell-sized liposomes, the self-assembled phospholipid vesicles with bilayer membranes, have garnered substantial attention across various fields, particularly as cell mimics. In this study, we introduce a simplified method for rapidly producing single- and multicompartment liposomes using a common laboratory vortex mixer. The simplicity of our method has the potential to greatly facilitate artificial cell and tissue-related research, potentially leading to broader applications of liposomes.

In the Research Article by Munenori Numata and co-workers a dissipative self-assembly system powered by flow and light is demonstrated. Supramolecular co-polymerization and rolling-up from the forward polymer's end led to the creation of discrete micrometer-sized supramolecular architecture featuring both molecular-level inner complexity and long-range order over molecular scale.

Coacervates have been investigated as protocells or synthetic cells, as well as subcellular compartments for the creation of new materials, thus bridging the gap between living and non-living systems in materials science, synthetic biology, and bioengineering. Given the design flexibility and simplicity of coacervates, along with the functionality and complexity of natural cells, the interfacing of complex coacervates with natural cells is considered significant for various biotechnological and biomedical applications. In this review, the fundamental mechanisms and underlying theories of coacervate systems are introduced. Recent efforts to interface coacervates with natural cells are summarized in three key scenarios: (i) the integration of coacervates with natural cell components for the living material assembly into protocells; (ii) communication between therapeutic synthetic cells and natural cells for drug delivery and cell repair; and (iii) the formation of intracellular condensates for metabolic regulation, followed by the regulation of their phase transitions for pathological elucidation. Finally, the potential of coacervate-natural cell interfaces is discussed in the context of developing living/synthetic cell constructs, creating precise disease therapy strategies, and advancing programmable metabolic engineering networks.

Supramolecular systems are often designed such that a steady state exists. However, the ability to design systems with pre-determined changes in state can lead to highly dynamic materials, with evolving supramolecular structures and adaptable material properties. This approach is of great interest from the perspective of designing adaptive systems as well as from a broader systems chemistry perspective. Here, we report how a transient system can be altered to access different mechanical properties and transitions by varying the trigger and temperature. The aging of these systems is also explored, as the networks continually evolve long past the common cut-off point of analysis of one day. We therefore provide new insights into the control of transient gels, as well as an understanding as to the underpinning supramolecular structures and how they evolve with time.

The functions of living organisms are emergent from networks of biomolecules. In this review, we discuss the creation of synthetic life-like systems based on the interplay of peptides and porphyrins in the supramolecular chemical systems. In particular, we focus on the spatiotemporal control of self-assembly processes, which allows for the development of hierarchical structures for biomimetic catalysis and adaptive dynamics for stimulus-responsive structural transformations. Notably, when operating in a nonequilibrium regime–characterized by kinetic traps, feedback loops, and dissipative conditions–the structural landscape expands and system-level properties emerge, including transient catalysis, metabolic self-replication, and Darwinian-like evolution. Controlling these systems at the biointerface would facilitate intelligent therapeutic interventions in the anti-tumor phototherapy. Supramolecular systems chemistry provides a valuable framework for exploring new physicochemical spaces of peptides and porphyrins, and may offer distinct advantages and extensive applications across diverse fields.

Giant membrane vesicles (GUVs) and Giant plasma membrane vesicles (GPMVs) are used as models to study membrane properties. We conducted a comparative study to examine how reducing the volume of vesicles with different lipid compositions, solution symmetries, solution asymmetries, and membrane charges affects their morphology. We used three-dimensional visualization techniques to study the shape of the vesicles. Although the vesicles may not be perfectly spherical, they exhibit some fluctuations in their shape. To understand these variations, we used confocal image stacks for visualization. Our experimental observations show that the membrane′s charge influences the deflation of the GUVs in the presence of trans-bilayer sugar asymmetries. The lipid bilayers of our GUVs have a uniform distribution of lipids in both leaflets, indicating no asymmetry in lipid composition. We induce trans-bilayer asymmetries by exposing each leaflet of the bilayer to different solution compositions. We also estimated and compared the deformation of GPMV extracted from HEK-293 cells with trans-bilayer buffer asymmetries and inherent leaflet compositional asymmetry with biomimetic membranes.

Chemical gradients provide spatiotemporal signaling fields in various cellular processes, driving complex dynamic behaviours such as differentiation and spatial organization. Here we employ opposing gradients of two artificial morphogens (sodium dodecyl sulfate (SDS) and sodium phosphotungstate (polyoxometalate; POM)) to systematically investigate morphological differentiation in organized populations of coacervate microdroplet-based protocells. Using a matrix of 16 sets of counter-diffusive gradients, we classify the differentiated protocells into five phenotypes and encode their spontaneous organization into different spatially patterned protocell consortia using a 3-bit binary information system. We show that a predominant SDS gradient produces a diversity of differentiated phenotypes to generate complex spatially coded 2D protocell organizations. In contrast, a prevailing POM gradient decreases morphological differentiation, resulting in population homogenization. Our results improve our understanding of gradient concentration-dependent collective responses in synthetic microscale agents and provide a step to a new spatially resolved information encoding method with 3-bit binary outputs.

The input of energy can shift an isomerization reaction A⇌B away from equilibrium, but which way, in favor of A or in favor of B? The answer to this question lies in understanding kinetic asymmetry, a concept first discussed in the context of how energy from an oscillating or fluctuating perturbation can act in concert with a catalyst to drive a reaction away from equilibrium. The key theoretical result is the non-equilibrium pumping equality that generalizes the idea of the equilibrium constant to the non-equilibrium steady-state.

The construction of chemical reaction networks (CRNs) is a formidable challenge because of their holistic and nonlinear nature. One approach to constructing CRNs involves combining fragments with distinctive properties, known as network motifs. Thiol chemistry is widely used in the construction of CRNs, with motifs available for positive and negative feedback loops. However, a simple catalytic motif has been lacking. Here, we developed a pseudo-catalytic motif using the reaction between cystamine and organic thiocyanates, which operates through a nucleophilic chain mechanism. Although similar to thiol autocatalytic systems, this reaction does not involve a doubling of the number of thiol species at any stage. The reaction is high-yielding and produces 2-amino-2-thiazoline. Its pseudo-catalytic nature manifests itself in the nearly linear relationship between the reaction rate and the amount of free thiols added at the beginning of the reaction. We demonstrated that this reaction can be regulated by external, time-dependent thiol signals and integrated into larger CRNs. We believe that this system will be a valuable addition to thiol chemistry, enabling the construction of CRNs with interesting functionalities.

This work investigates the influence of dielectrophoretic forces on the structural features and the resulting aggregates of a chromogenic model system, peptide-diacetylene (D₃GV-DA) amphiphiles. Here, we systematically investigate how non-uniform electric fields impact the (i) peptide-directed supramolecular assembly stage and (ii) topochemical photopolymerization stage of polydiacetylenes (PDAs) in a quadrupole-based dielectrophoresis (DEP) device, as well as the (iii) manipulation of D₃GV-DA aggregates in a light-induced DEP (LiDEP) platform. The conformation-dependent chromatic phases of peptide-PDAs are utilized to probe the chain-level effect of DEP exposure after the supramolecular assembly or after the topochemical photopolymerization stage. Steady-state spectroscopic and microscopy analyses show that structural features such as the chirality and morphologies of peptidic 1-D nanostructures are mostly conserved upon DEP exposure, but applying mild, non-uniform fields at the self-assembly stage is sufficient for fine-tuning the chromatic phase ratio in peptide-PDAs and manipulating their aggregates via LiDEP. Overall, this work provides insights into how non-uniform electric fields offer a controllable approach to fine-tune or preserve the molecularly preset assembly order of DEP-responsive supramolecular or biopolymeric assemblies, as well as manipulate their aggregates using light projections, which have future implications for the precision fabrication of macromolecular systems with hierarchical structure-dependent function.