Ketyl radical and amino radical anions, valuable reactive intermediates for C-C bond-forming reactions, are accessible through a C=O/C=NR umpolung. However, their utilization in catalysis remains largely underdeveloped owing to the high reduction potential of carbonyl compounds and imines. In the context of photoredox catalysis, tertiary amines are commonly employed as sacrificial co-reducing agents. Herein, an additional role of the amine is proposed, in which it is essential for the organocatalytic substrate activation. The combination of photoredox catalysis and carbonyl/imine activation enables the reductive coupling of aldehydes, ketones, and imines under mild reaction conditions.

DNA has traditionally been used for the programmable design of nanostructures by exploiting its sequence-defined supramolecular recognition. However, control on larger length scales or even hierarchical materials that translate to the macroscale remain difficult to construct. Here, we show that the polymer character of single-stranded DNA (ssDNA) can be activated via a nucleobase-specific lower critical solution temperature, which provides a unique access to mesoscale structuring mechanisms on larger length scales. We integrate both effects into ssDNA multiblock copolymers that code sequences for phase separation, hybridization and functionalization. Kinetic pathway guidance using temperature ramps balances the counteracting mesoscale phase separation during heating with nanoscale duplex recognition during cooling to yield a diversity of complex all-DNA colloids with control over the internal dynamics and of their superstructures. Our approach provides a facile and versatile platform to add mesostructural layers into hierarchical all-DNA materials. The high density of addressable ssDNA blocks opens routes for applications such as gene delivery, artificial evolution or spatially encoded (bio)materials.

We introduce divalent 3D DNA origami cuboids as truly monodisperse colloids and harness their ability for precision functionalization with defined patches and defined numbers of supramolecular binding motifs. We demonstrate that even adamantane/β‐cyclodextrin host/guest inclusion complexes of moderate association strength can induce efficient supracolloidal fibrillization at high dilution of the 3D DNA Origami as a result of cooperative multivalency. We show details on the assembly of Janus and non‐Janus 3D DNA origami into supracolloidal homo‐ and heterofibrils with respect to multivalency effects, electrostatic screening, and stoichiometry. We believe that the merger of 3D DNA origami with colloidal self‐assembly and supramolecular motifs provides new synergies at the interface of these disciplines to better understand multivalency effects, to promote structural complexity, and add non‐DNA assembling and switching mechanisms to DNA nanoscience.

Nanostructures derived from amphiphilic DNA–polymer conjugates have emerged prominently due to their rich self‐assembly behavior; however, their synthesis is traditionally challenging. Here, we report a novel platform technology towards DNA–polymer nanostructures of various shapes by leveraging polymerization‐induced self‐assembly (PISA) for polymerization from single‐stranded DNA (ssDNA). A “grafting from” protocol for thermal RAFT polymerization from ssDNA under ambient conditions was developed and utilized for the synthesis of functional DNA–polymer conjugates and DNA–diblock conjugates derived from acrylates and acrylamides. Using this method, PISA was applied to manufacture isotropic and anisotropic DNA–polymer nanostructures by varying the chain length of the polymer block. The resulting nanostructures were further functionalized by hybridization with a dye‐labelled complementary ssDNA, thus establishing PISA as a powerful route towards intrinsically functional DNA–polymer nanostructures.

Soft photonic materials are important for sensors, displays, or energy management and have become switchable under static equilibrium conditions by integration of responsive polymer features. The next step is to equip such materials with the ability for autonomously dynamic and self-regulating behavior, which would advance their functionality and application possibilities to new levels. Here, this study shows the system integration of a nonlinear, biocatalytic pH-feedback system with a pH-responsive block copolymer photonic gel, and demonstrates autonomous transient memories, remotely controlled signal propagation, and sensing. This study utilizes an enzymatic switch to program the lifetime of the reflective state of a photonic gel, and induces propagation of pH-waves extinguishable by illumination with UV-light. The described combination of nonlinear chemistry and responsive photonic gels opens pathways toward out-of-equilibrium photonic devices with active and autonomous behavior useful for sensing, computation, and communication.

There exists a critical need in biomedical molecular imaging and diagnostics for molecular sensors that report on slight changes to their local microenvironment with high spatial fidelity. Herein, a modular fluorescent probe, termed StyPy, is rationally designed which features i) an enormous and tunable Stokes shift based on twisted intramolecular charge transfer (TICT) processes with no overlap, a broad emission in the far‐red/near‐infrared (NIR) region of light and extraordinary quantum yields of fluorescence, ii) a modular applicability via facile para‐fluoro‐thiol reaction (PFTR), and iii) a polarity‐ and viscosity‐dependent emission. This renders StyPy as a particularly promising molecular sensor. Based on the thorough characterization on the molecular level, StyPy reports on the viscosity change in all‐DNA microspheres and indicates the hydrophilic and hydrophobic compartments of hybrid DNA‐based mesostructures consisting of latex beads embedded in DNA microspheres. Moreover, the enormous Stokes shift of StyPy enables one to detect multiple fluorophores, while using only a single laser line for excitation in DNA protocells. The authors anticipate that the presented results for multiplexing information are of direct importance for advanced imaging in complex soft matter and biological systems.

Microgels are soft colloids that showr esponsive behavior and are easy to functionalizef or applications.T hey are considered key components for future smart colloidal material systems.H owever,s of ar microgel systems have almost exclusively been studied in classical responsive switching settings using external triggers,w hile internally organized, autonomous control mechanisms as found in supramolecular chemistry and DNAn anotechnology relying on fuel-driven out-of-equilibrium concepts have not been implemented into microgel systems.H ere,w ei ntroduce chemically fueled transient volume phase transitions (VPTs) for poly(methacrylic acid) (PMAA) microgels,w here the collapsed hydrophobic state can be programmed using the fuel concentration in ac yclic reaction network. We discuss details of the system behavior as af unction of pH and fuel amount, unravel kinetically trapped regions and showcase transient encapsulation and time-programmed release as afirst application.

Scaffold-based lattice-engineered 3D DNA origami is a powerful and versatile technique for the rational design and build-up of arbitrarily structured and monodisperse DNA-based 3D nanoobjects. Relying on the unsurpassed molecular programmability of sequence-specific DNA hybridization, a long DNA single strand (termed scaffold) is assembled with many short single-stranded oligomers (termed staples), which organize the scaffold into a 3D lattice in a single step, thereby leading to 3D nanoparticulate structures of the highest precision in high yields. Applications of 3D DNA origami are increasingly wide-spread and interface with numerous fields of sciences, for example, anisometric or anisotropically functionalized nanoparticles, fundamental investigations of superstructure formation, biomedicine, (bio)physics, sensors, and optical materials. This Minireview discusses the fundamentals and recent advances from structure formation to selected applications, with a mission to promote cross-disciplinary exchange.