Highlight-Publications

Using hexafluoro-isopropanol (HFIP) as a solvent can enhance chemical reaction rates in a spectacular manner, but why this happens is still largely unknown. Researchers at the University of Amsterdam’s Van ’t Hoff Institute for Molecular Sciences (HIMS), together with colleagues at the Université libre de Bruxelles, and the Max Planck Institute for Polymer Research (Mainz, Germany) have now established that the small size and fast collective dynamics of hydrogen-bonded clusters in HFIP help to enhance its chemical activity. In a paper just accepted by Angewandte Chemie, they describe how they unravelled the subtle workings of the ‘miracle solvent’ using state-of-the-art spectroscopy experiments. [more]

Simultaneously achieving high-quality uniform alignment over a large area and high-resolution bespoke spatial patterning of molecular orientation is long-sought yet challenging, despite the essential role in generating bio-inspired organic systems, miniaturized light modulation, integrated photonic circuits, directed excitation energy transfer and relaxation, etc. Within this featured paper, Dr. Yuping Shi at MPI-P and his coworkers report a research breakthrough made along this line, in terms of the successful fabrication of large-area extended monodomain (semi-)crystals of semiconducting polymers via the development of a novel photoalignment technique. [more]

Here we demonstrate a novel nanocarrier-based vaccine combining the type I interferon-triggering STING agonist diamidobenzimidazole (diABZI) compound 3 and the well-established TLR7/ 8 agonist resiquimod (R848). Encapsulation of both adjuvants into polymeric nanocapsules enables the simultaneous transport of immunostimulatory molecules with tumor antigens. [more]

A small-scale organic neuromorphic circuit adaptively processes multimodal sensory stimuli, enabling a robotic arm to avoid potentially dangerous objects.​ [more]

​A team led by Hans-Jürgen Butt at the Max Planck Institute for Polymer Research has discovered that altering the thickness of nano-scale polymer layers, even within a range of 10 nm, can significantly influence drop motions. They found a 'magic thickness' of 5 nm for polydimethylsiloxane (PDMS) which results in the lowest interfacial friction between a sliding water drop and the PDMS layer. This finding is of great significance for promoting the application of fluoride-free nano coatings in liquid environments. [more]

When water droplets move over a hydrophobic surface, they and the surface become oppositely charged by what is known as slide electrification. This effect can be used to generate electricity, but the physical and especially the chemical processes that cause droplet charging are still poorly understood. Here, we investigate the influence of the chemistry of surface (coating) and bulk (substrate) on the slide electrification. We show that the charge of the first droplet depends on both coating and substrate chemistry. For a fully fluorinated or fully hydrogenated monolayer on glass, the influence of the substrate on the charge of the first droplet is negligible. In a later the state, the chemistry of the substrate dominates. Charge separation can be considered as an acid base reaction between the ions of water and the surface. By exploiting the acidity (Pearson hardness) of elements such as aluminum, magnesium, or sodium, a positive saturated charge can be obtained by the counter charge remaining on the surface. With this knowledge, the droplet charge can be manipulated by the chemistry of the substrate. [more]

The generation of persistent, stable free radicals is a key feature of eumelanin physiochemistry. Scientists carried out EPR and IR to study the comproportionation reaction of eumelanin. The investigation of the formation of eumelanin radicals in the complex, dynamic and inhomogeneous environment of living cells has not yet been achieved, due to the lack of sensitivity of conventional detection methods. To gain a more comprehensive understanding of their biological functions in a spatiotemporal context, we developed a radical sensing and detecting nanodiamond (RGS-ND) quantum sensor that allows in situ real-time detection of the radicals present in eumelanin granules, with a particular emphasis on accurately quantifying the number of radicals formed inside cells. [more]

Nanographenes, synthesized with biocompatibility and functionalization groups, hold great promise as fluorophores for optical super-resolution microscopy. Such molecules exhibit excellent photo-blinking properties across diverse environments, including air, phosphate-buffered saline, and acidic or basic conditions. In our study, we demonstrated their applicability in materials imaging, live-cell imaging, and functional analysis of neurons at the nanometer scale.

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We present a relatively simple aqueous proton-based memristive device based on a calcium fluoride (CaF₂)-supported monolayer graphene in contact with bulk water. The device design is enabled by molecular-level insights into the memristive ion/water dynamics and the corresponding synaptic phenomena in this aqueous memristive device. The memristive behavior arises from the fast proton transfer across the graphene and the relatively slow diffusion process of protons. Despite the device's simplicity, this aqueous device exhibits long-term and tunable memory (from 60 seconds to 6000 seconds) and promising potential for large-scale integration and multiplication. [more]

Artificial organelles made of dipeptide coacervates enable bioorthogonal catalysis inside cells. These coacervates provide a stable, biocompatible, and hydrophobic microenvironment that effectively encapsulates and enhances the efficiency of transition metal-based catalysts in aqueous environments. When incorporated into cells, they function as active organelles that facilitate specific non-biological internal chemical reactions. [more]

A consortium of scientists led by University of Mons and MPI for Polymer Research have studied the temperature dependent hole mobility of two structurally similar organic semiconductors: DNTT, and its alkylated derivative, C8-DNTT-C8. They demonstrated that the charge delocalization – directly linked to charge mobility - is larger in C8-DNTT-C8 than in DNTT due to the distinctive band structure of the former system. This study indicates the possibility to reach extremely high mobilities of organic crystals by appropriately engineering the material properties. [more]

​Photocatalytic nanoparticles are presented that are active and well-dispersed under acidic conditions but aggregate instantly upon elevation of pH. These responsive photocatalytic polymers can be used in various photocatalytic transformations, including Cr^VI reduction and photoredox alkylation of an indole derivative. The particles could be readily recycled, allowing multiple successive photocatalytic reactions with no clear loss in activity. [more]

A delicate balance between preferential interaction, hydrogen bonding and dipole-dipole interactions determines polyalanine α-helix (un)folding in aqueous urea. This study clarifies and reconciles existing literature and highlights an operational understanding of polypeptide interactions in binary solutions, which is critical for designing biocompatible materials. [more]

Finding potential organic alternatives to traditional silicon-based semiconductors has been a long-standing goal in the field of organic chemistry. A work recently published in ‘Nature Materials’ reports highly conjugated two-dimensional conjugated polymers with exceptionally high short-range charge mobility of approaching cm²V^-1s^-1 at room temperature.
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A study on van der Waals heterostructures unveils that the photoinduced processes at the interface between the different materials can be modified by electrically controlling the occupancy of the interfacial defects. The findings are just published in Nano Letters.
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Living organisms compartmentalize their catalytic reactions in membranes for increased efficiency and selectivity. Here we developed a mild approach for in situ encapsulating enzymes in aqueous-core silica nanoreactors that can mimic the basic structure and reactions of organelles in the eukaryotic cells. [more]

Ion-specific interfacial potentials at the silica-water interface are compensated by water alignment [more]

Sensorimotor augmentation: a stretchable remote tactile device with 3D depth-of-perception equips a biological model with the sense of electroreception.  [more]

Controlling crystal growth and reducing the number of grain boundaries are crucial to maximize the charge carrier transport in organic–inorganic perovskite field-effect transistors (FETs). Herein, the crystallization and growth kinetics of 2D perovskite, were effectively regulated by the hot-casting method. Our work provides an important insight into the grain engineering of 2D perovskites for high-performance FETs. [more]

Preventing the accumulation of nanocarriers is of high importance to promote nanomedicines and enable their application, for instance, in immunodrug delivery. In this paper, polycarbonate-based nanogels are introduced as promising gradually hydrolyzing carrier system that allow a transient delivery of immune stimulatory cues into lymph nodes. [more]

This review article presents recent advances in the field of bottom-up synthetic biology, with a focus on the development of complex synthetic cells from simpler functional modules. The state of the art in this field is rich with new materials, strategies, and methods that provide a comprehensive toolbox to researchers interested in developing life-like systems. Our review article provides a critical collection of selected examples from the synthetic bottom-up biology toolbox. The information in our review article is organized from bottom to top, with basic modules presented first before discussing integrated systems. This review article will help researchers understand the current challenges in the field of bottom-up synthetic biology and inspire new technological applications in biomedicine, tissue engineering, and life-like materials chemistry. [more]

In this review, our group critically discuss chemical concepts to build synthetic architectures in cells and also present strategies that exploit various complex cellular environments to alter biological functions. Unlike conventional biological tools, the development of chemistry-based platform is in its infancy as we have only begun to understand few key processes involved in structural dynamics and equilibrium. Hence, there is a huge gap in elucidating molecular and macromolecular mechanisms that explains the impact these structures have on biological systems. As such, this review seeks to inspire the community and rally efforts to explore the uncharted grounds of structural based functions. [more]

Macrophages play an important role in the progression of liver fibrosis. In this paper, biodegradable nanogel particles have been designed to deliver clinically approved bisphosphonates into fibrotic livers and stop disease progression by changing the activity of macrophages. [more]

MXenes, firstly described in 2011, are a relatively new class of layered materials, each layer consisting of a few atoms of transition metal carbides and/or nitrides, e.g. Ti₃C₂T_x. MXenes have attracted considerable research attention for electronics and electrochemical applications, benefiting from their outstanding electrical and ionic transport properties. However, the nature of charges which can move freely in the material – so-called “free electrons” - and their transport mechanism in MXenes have remained elusive. In the past, strongly conflicting charge transport mechanisms have been proposed. New research shows that a free electron in MXenes displaces the atoms in the material's lattice: the electron is “dressed” by a local lattice deformation, extending over several lattice constants. This transforms the electron into a polaron, a quasi-particle, which plays a crucial role in determining the electrical conductivity of MXenes. [more]

Dual responsive dynamic covalent peptide tags exhibiting cooperative effects are tailored to control stability of bioconjugates and their release in tumor-like microenvironment. [more]

​Polymer engineering at the nanoscale has now a greater toolbox to construct 3-D architectures that are unattainable by conventional polymerization technologies. Using folded DNA origami as a template, polymers can be grown in patterns and assimilate a designated shape. Combined with multi-wavelength photopolymerization methods, we show that spatial and temporal control over polymer nanostructures can be made accessible to the broad scientific community. [more]

In this study, we have described the construction of synthetic nano-organelles for the regulation of enzymatic reactions in multi-compartmentalized systems. To do that, we have designed silica nano-capsules that can precisely encapsulate different enzymes, allowing the composition of the capsules to be adjusted. The outcome and efficiency of the multistep enzymatic cascade reactions depended on the number and type of nano-organelles present in the system. Moreover, the robustness of silica nano-organelles enabled their encapsulation into giant polymeric vesicles, resulting in multi-compartment bioreactors that mimic the structure of natural cells. [more]

In a study published in “Science Advances”, employing THz spectroscopy Zhang et al. report excess energy-dependent highly mobile hot holes in Cs2AgBiBr6 double perovskites. The finding could be relevant for utilizing Cs2AgBiBr6 for hot carrier-based optoelectronic devices. [more]

In a review now published in Nature Review Chemistry, Grazia Gonella et al. present results on the interaction of water molecules in contact with different types of charged or electrified interfaces, ranging from metals over oxides to biomembranes. While research on such aqueous interfaces is vital to very different communities, e.g. biophysics, electrochemistry, and geochemistry, the authors show the essential similarity of the different systems studied in these disciplines. They discuss open questions regarding the molecular picture of the interfacial organization and the preferential alignment of water molecules as well as the structure of water molecules and ion distributions at different charged interfaces. [more]

A study published in “ACS Nano” investigates the mechanism governing the cooling dynamics of photo-excited charge carriers in graphene-based structures, which are interesting candidates for future optoelectronic devices. This research was performed by a team of scientists from Barcelona, Milan, and Mainz, together with other researchers from Spain, Italy, Germany, UK, Belgium, and China.  [more]

Frost is a frequent encounter during winter.  It emerges whenever warm and humid air meets cold surfaces, e.g. morning dew frost. While frost is often perceived as mesmerizing and beautiful, it can create serious problems with infrastructure, crops or process machinery (valves, coils, cooling fins, etc.). Strategies such as heating or chemical anti-frost agents are energetically costly and harmful for the environment.   [more]

When nanomedicines are injected into the blood stream, biomacromolecules such as proteins present in the blood rapidly adsorb to their surfaces. The coverage of protein corona may shield the modified surface functionalities of nanomedicines, and hence imparts detrimentally their efficacy. Covalently attaching polyethylene glycol (PEG), a hydrophilic polymer, is the gold standard for reducing protein adsorption on nanocarriers. However, the role of polymer conformation on protein corona on nanoparticles with low protein affinity still needs to be unraveled. [more]

Perovskites are a recently re-discovered material class with excellent optoelectronic properties. For example, solar cells with record efficiencies have recently been prepared using perovskites. An important figure of merit for perovskites is the mobility of charges, i.e. electrons and holes, following the absorption of photons. Despite the promise of the material, many questions remain regarding the nature and mobility of charge carriers in perovskites. [more]