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Solid interfacing biomaterials is a crucial aspect of bionanotechnology and important for applications such as biosensing. Because of their potentially large contact area, flat solenoidal proteins are ideal scaffolds for designing proteins binding to surfaces of man-made solids such as minerals, metals, and plastics. To explore this opportunity, a naturally occurring flat solenoidal protein: the Rhagium inquistor Antifreeze Protein from the insect Rhagium inquisitor is re-designed. By mutating 4, 6, and 10 out of its 4 × 5 arrays of threonines into arginines, it have arrived at the silica-binding proteins RiSiBP-4, RiSiBP-6, and RiSiBP-10. Variants with increasing numbers of arginines bind stronger to silica, but are also less stable and increasingly difficult to produce. It is found that the RiSiBP-6 variant binds strongly to silica yet still has good stability and easy production. It is shown that sfGFP-RiSiBP-6 fusions allow for the functional display of a monolayer of sfGFP cargo on silica surfaces, suggesting the general usefulness of flat solenoidal proteins as scaffolds for designing solid-binding proteins.

The characterization of polymeric materials is key towards the understanding of structure–activity relations and therefore for the rational design of novel and improved materials for a myriad of applications. Many microscopy techniques are currently used, with electron microscopy, fluorescence microscopy, and atomic force microscopy being the most relevant. In this perspective paper, we discuss the use of correlative imaging, that is, the combination of multiple imaging methodologies on the same sample, in the field of polymeric materials. This innovative approach is emerging as a powerful tool to unveil the structure and functional properties of biological and synthetic structures. Here we discuss the possibilities of correlative imaging and highlight their potential to answer open questions in polymer science.

Biological processes rely on transient interactions that govern assembly of biomolecules into higher order, multi‐component systems. A synthetic platform for the dynamic assembly of multicomponent complexes would provide novel entries to study and modulate the assembly of artificial systems into higher order topologies. Here, we establish a hybrid DNA origami‐based approach as an assembly platform that enables dynamic templating of supramolecular architectures. It entails the site‐selective recruitment of supramolecular polymers to the platform with preservation of the intrinsic dynamics and reversibility of the assembly process. The composition of the supramolecular assembly on the platform can be tuned dynamically, allowing for monomer rearrangement and inclusion of molecular cargo. This work should aid the study of supramolecular structures in their native environment in real‐time and incites new strategies for controlled multicomponent self‐assembly of synthetic building blocks., DNA origami platforms were used to assemble synthetic supramolecular polymers, retaining their dynamic nature with control over monomer composition and loading and dynamic exchange of molecular cargo. The DNA origami‐templated self‐assembly allows for novel strategies for controlled multicomponent self‐assembly and characterization of synthetic supramolecular systems.

Reversibly programmable photonic integrated circuits (PICs) that can facilitate multifunctionality have been long sought after to deliver user-level design flexibility. Issues like complicated control, continuous power consumption, and high optical losses hinder their large-scale adaptation. In this work, a novel approach toward programmable photonics using a responsive polyelectrolyte multilayer (PEM) cladding is presented. Reversible (de)swelling of PEMs by consecutive exposure to acidic and neutral pH solutions yields highly contrasting refractive index changes in the dry film. Utilizing this effect, an easily applied technique for programming photonic integrated devices with two different approaches, complete and area-selective deposition, for several reversible cycles is demonstrated. These devices operate at two distinct states that are virtually lossless and nonvolatile. This proof-of-concept demonstration is suitable for various photonic integration platforms to facilitate reconfigurable photonic processors, static memories, and fine-tuning of fabrication related limitations. Therefore, these results are the first step toward PEM-assisted reversibly programmable multipurpose PICs for low-cost mass production.

Responsive materials, which can adapt and operate autonomously under dynamic conditions, are a stepping stone towards functional, life-like systems inspired by fueled self-assembly processes in nature. Complex coacervate core micelles (C3Ms) comprising oppositely charged macromolecules constitute a novel class of polymeric micelles ideally suited for use as responsive nanoscopic delivery vehicles of hydrophilic and hydrophobic cargo. To fully exploit their potential, it is important that the C3Ms form and fall apart in an autonomous fashion as orchestrated by dynamic cues in their environment. Herein a means to temporally program the self-regulated C3M coassembly pathway, using a modulated base-catalyzed feedback system, is presented. Incorporated in the C3Ms is a pH responsive polyfluorene-based conjugated polyelectrolyte (CPF) as a building block and trace amounts of a molecular sensor (doxorubicin HCl) as cargo, both of which report on micellar coassembly and disassembly via binding-induced fluorescence quenching. CPF additionally reports on the pH of its microenvironment as its pH-dependent conformational states are mirrored in the transitions of its vibronic bands. This experimental design enables one to monitor solution pH, C3M disassembly and reassembly, as well as cargo release and recapture noninvasively in a closed system with real time florescence experiments.