ChemSystemsChem最新文献

The cover picture shows a scanning electron micrograph of self-organized chemical garden tubes. These calcium-based hollow structures are composed of porous walls separating an alkaline exterior liquid and acidic, metal salt interior solution. Natural analogs to this classic chemistry experiment are hydrothermal vents found at the base of the ocean. Their structures are composed of mineral walls which separate two disparate chemical environments maintaining a far-from-equilibrium setting. More in theResearch Article by Pamela Knoll and Corentin C. Loron.

The origin of life, being one of the most fascinating questions in science, is increasingly addressed by interdisciplinary research. In addition to developing plausible chemical models for synthesizing the first biomolecules from prebiotic building blocks, searching for suitable and plausible non-equilibrium boundary conditions that drive such reactions is thus a central task in this endeavor. This perspective highlights the remarkably simple yet versatile scenario of heat flows in geologically plausible crack-like compartments as a habitat for prebiotic chemistry. Based on our recent findings, it is discussed how thermophoretically driven systems offer insights into solving key milestones in the origin of life research, such as the template inhibition problem, prebiotic symmetry breaking, and the promotion of prebiotic chemistry by selective enrichment of biochemical precursors. Our results on molecular-selective thermogravitational accumulation, heat flow-induced pH gradients, and environmental cycles are put in the context of other approaches to non-equilibrium systems and prebiotic chemistry. The coupling of heat flows to chemical and physical boundary conditions thus opens up numerous future experimental research avenues, such as the extraction of phosphate from geomaterials or the integration of chemical reaction networks into thermal non-equilibrium systems, offering a promising framework for advancing the field of prebiotic chemistry.

Owing to their property to alter their surface-activity upon the irradiation with light, photoswitchable surfactants have gained tremendous interest in colloidal science. Their mere addition to a colloidal system allows, e. g., to obtain control over polyelectrolytes, micro- and nanoscale particles or emulsions. Most literature examples focus on azobenzene-based, or related, systems, which employ a photoisomerization reaction for switching. Other structures, such as spiropyrans, play a subordinate role, although they have gained increasing attention over the past few years. In this perspective article, we want to provide an overview about existing systems of photoswitchable surfactants. We address the issue that alternative photoswitches are given less attention, and what benefits surfactants could possess that are based on said switchable units. With our contribution, we want to broaden the view on stimuli-responsive surfactants – and to provide a guideline for the design of novel structures.

The front cover illustrates cell-like functional molecular systems based on DNA nanotechnology and lipid vesicles. The base-specific interactions of DNA enable the construction of various functional components that can be integrated into lipid vesicles, aiming to create artificial molecular systems comparable to, or even surpassing, natural molecular systems, such as living cells. The Review by Y. Sato describes the latest achievements in functions realized through the combination of DNA nanotechnology and lipid vesicles.

We previously reported collective behavior in colloidal aggregates of silver phosphate in H₂O₂ and under UV light. Diffusiophoretic interactions between aggregates lead to non-linear behavior such as oscillations and synchronization, in which oscillation frequencies increase with H₂O₂ concentration. The aggregates transition between schooling and dispersed behaviors with incipient spatiotemporal correlations. We identified a kinetic model that maps the chemical species that are thought to underlie non-linear phenomena in the colloidal aggregates, i. e. adsorbed oxygen species *OOH⁻ and *O. We investigate the emergent dynamics for the simplest case, the coupling of two otherwise bistable clusters. Two coupling schemes are proposed and we find that – depending on whether the coupling is excitatory or inhibitory – the clusters may oscillate with zero or π phase shift.

An E. coli cell contains ~2500 different chemicals which combine into an ordered biochemical reaction network out of which emerges a living system. A chemist taking 2500 different chemicals from a laboratory chemical cabinet and combining them together will likely cause an explosive disaster and produce an intractable chemical sludge. Systems Chemistry aspires to construct systems whose complexity rivals that of life. However, to do this we will need to learn how to combine hundreds or thousands of different chemicals together to form a functional system without descending into a disordered chemical sludge. This is the Many-Chemicals Problem of Systems Chemistry. I explore a key strategy life employs to overcome this challenge. Namely, the combination of kinetically stable and thermodynamically activated molecules (e. g. ATP) with enzyme catalysts (e. g. histidine kinases). I suggest how the strategy could have begun at the origin of life. Finally, I assess the implications of this strategy for Systems Chemistry and how it will enable systems chemists to construct systems whose complexity rivals that of life.