Ilja Voets

• Professor (Full) at Eindhoven University of Technology

The ingress of water-soluble aggressive species is a major cause to the reduced service life of concrete structures. Bulk modification by adding hydrophobic agents in the cementitious materials is commonly applied to reduce water penetration into the concrete matrix. However, conventional hydrophobic modifications of concrete are associated with se...

Macroscopic material properties are ultimately determined by the microstructural arrangement of building blocks. Bottom-up material fabrication routes exploit this central dogma by reverse-engineering the required building blocks from a targeted structure or property. Despite the plethora of available building blocks, bridging the gap between the m...

Worldwide, over 26 million patients suffer from heart failure (HF). One strategy aspiring to prevent or even to reverse HF is based on the transplantation of cardiac tissue-engineered (cTE) constructs. These patient-specific constructs aim to closely resemble the native myocardium and, upon implantation on the diseased tissue, support and restore c...

Industrial and household products, such as paints, inks and cosmetics usually consist of mixtures of macromolecules that are disperse in composition, in size and in monomer sequence. Identifying structure-function relationships...

Regulation of DNA-templated processes such as gene transcription and DNA repair depend on the interaction of a wide range of proteins with the nucleosome, the fundamental building block of chromatin. Both solution and solid-state NMR spectroscopy have become an attractive approach to study the dynamics and interactions of nucleosomes, despite their...

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...

Hypothesis Despite advances in understanding the R5 (SSKKSGSYSGKSGSKRRIL) peptide-driven bio-silica process, there remains significant discrepancies regarding the physicochemical characterization and the self-assembling mechanistic driving forces of the supramolecular R5 template. This paper investigates the self-assembly of R5 as a function of mon...

We report on the self‐assembly in water of a set of bis‐urea amphiphiles. A range of techniques, including dynamic light scattering, Cryo‐TEM, SAXS, and MS are used to study the effect of structural variation on the morphology of the assemblies. The length, dispersity, and end‐group of the ethylene glycol hydrophilic part of the molecule, as well a...

In natural systems, temperature‐induced assembly of biomolecules can lead to the formation of distinct assembly states, created out of the same set of starting compounds, based on the heating trajectory followed. Until now it has been difficult to achieve similar behavior in synthetic polymer mixtures. Here, a novel pathway‐dependent assembly based...

A polymeric corona consisting of an alkyl-glycolic acid ethoxylate (C X EO Y ) surfactant offers a promising approach toward endowing proteins with thermotropic phase behavior and hyperthermal activity. Typically, preparation of protein-surfactant biohybrids is performed via chemical modification of acidic residues followed by electrostatic conjuga...

While the impact of compositional parameters such as block length and ionic content on the micellization of (polymeric) amphiphiles is widely investigated, the influence of monomer sequence has received far less attention until recently. Here, we report the synthesis of two sequence-controlled polyurethane ionomers (PUIs) prepared via a stepwise co...

Regulation of DNA-templated processes such as gene transcription and DNA repair depend on the interaction of a wide range of proteins to the nucleosome, the fundamental building block of chromatin. Both solution and solid-state NMR spectroscopy have become an attractive approach to study the dynamics and interactions of nucleosomes, despite their h...

Understanding the mechanisms by which natural anti-freeze proteins protect cells and tissues from cold could help to improve the availability of donor organs for transplantation.

Electrostatically coassembled micelles constitute a versatile class of functional soft materials with broad application potential as, for example, encapsulation agents for nanomedicine and nanoreactors for gels and inorganic particles. The nanostructures that form upon the mixing of selected oppositely charged (block co)polymers and other ionic spe...

The core of micelles self-assembled from amphiphiles is hydrophobic and contains little water, whereas complex coacervate core micelles co-assembled from oppositely charged hydrophilic polymers have a hydrophilic core with a high water content. Co-assembly of ionic surfactants with ionic-neutral copolymers yields surfactant–copolymer complexes know...

Synthetic stimuli responsive supramolecular polymers attract increasing interest for their ability to mimic the unique properties of natural assemblies. Here we focus on the well‐studied benzene‐1,3,5‐tricarboxamide (BTA) motif, and substitute it with two (S)‐3,7‐dimethyloctyl groups and an azobenzene photoswitch. We demonstrate the UV (λ=365 nm) i...

Colloidal structures and lattices made of patchy particles with chemically distinct lobes are formed by exploring site-specific depletion forces. This approach introduces a simple route to assemble colloidal superlattices.

Despite a growing understanding of factors that drive monomer self-assembly to form supramolecular polymers, the effects of aromaticity gain have been largely ignored. Herein, we document the aromaticity gain in two different self-assembly modes of squaramide-based bolaamphiphiles. Importantly, O → S substitution in squaramide synthons resulted in...

Self-assembly of block copolymers in solution is a topic of great interest in polymer science due to the potential for applications as a drug carrier system. In bulk, fully discrete polymers have been shown to self-assemble in extremely well-defined structures, but the effect of full discreteness on self-assembly in solution is less known. Furtherm...

Modulation of protein-protein interactions (PPIs) with small-molecules is a promising conceptual approach in drug discovery. In the area of bacterial colonization, PPIs contribute to adhesin-mediated biofilm formation that cause most infections. However, the molecular basis underlying these adhesin-ligand interactions is largely unknown. The 1.5-MD...

Silica materials attract an increasing amount of interest in (fundamental) research, and find applications in, for example, sensing, catalysis, and drug delivery. As the properties of these (nano)materials not only depend on their chemistry but also their size, shape, and surface area, the controllable synthesis of silica is essential for tailoring...

As an emerging alternative cementitious binder, alkali activated slag (AAS) is gaining great attention, but considerable shrinkage caused by alkali activation and drying limit its potential applications. Herein, we demonstrate that the addition of an environmentally benign biofilm, cultured from B. subtilis, mitigates both the autogenous and drying...

The co-assembly of ionic-neutral block copolymers with oppositely charged species produces nanometric colloidal complexes, known, among other names, as complex coacervates core micelles (C3Ms). C3Ms are of widespread interest in nanomedicine for controlled delivery and release, whilst research activity into other application areas, such as gelation...

We present a simple way to build up well-controlled coacervate-core dendrimicelles by assembly of anionic PAMAM dendrimers with a cationic-neutral diblock copolymer. Upon increasing pH, the formation of micellar structures shows constant size but the number of dendrimer molecules incorporated in one micelle decreases, following the charge stoichiom...

Transient assembled structures play an indispensable role in a wide variety of processes fundamental to living organisms including cellular transport, cell motility, and proliferation. Typically, the formation of these transient structures is driven by the consumption of molecular fuels via dissipative reaction networks. In these networks, building...

In article number 2000325, Ilja K. Voets, Oded Raz and co‐workers explore a method for programmable photonics using a responsive polyelectrolyte multilayer (PEM) cladding. Reversible swelling of the PEM by consecutive exposure to acidic and neutral pH solutions yields control over the porosity of the film. The resulting refractive index changes are...

Antifreeze proteins and antifreeze glycoproteins (AF(G)Ps) enable the survival of various cold-adapted organisms in freezing and subfreezing habitats by preventing the macroscopic growth of ice crystals. Regardless of their great structural diversity are all AF(G)Ps capable to adhere to growing ice crystals, a quality that is essential for their bi...

Pickering emulsions are increasingly applied in the production of medicines, cosmetics and in food technology. To apply Pickering emulsions in a rational manner it is insufficient to examine properties solely on a macroscopic scale, as this does not elucidate heterogeneities in contact angles (θ) of individual particles which may have a profound im...

Frost weathering of porous materials caused by seasonal temperature changes is a major source of damage to the world’s infrastructure and cultural heritage. Here we investigate poly(vinyl alcohol) (PVA) addition as a means to enhance the freeze–thaw durability of concrete without compromising its structural or mechanical integrity. We evaluate the...

One of the most appealing features of supramolecular assemblies is their ability to respond to external stimuli due to their non-covalent nature. This provides the opportunity to gain control over their size, morphology and chemical properties and is key towards some of their applications. However, the design of supramolecular systems able to re-sp...

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 photon...

Controlling the transient self‐assembly of (macro)molecular building blocks is of fundamental interest, both to understand the dynamic processes occurring in living systems and to develop new generations of functional materials. The subtle interplay between different types of physicochemical interactions, as well as the possible reaction pathways,...

Engineered living materials have the potential for wide-ranging applications such as biosensing and treatment of diseases. Programmable cells provide the functional basis for living materials, however, their release into the environment raises numerous biosafety concerns. Current designs that limit the release of genetically engineered cells typica...

In this manuscript we begin by preparing bulk Pickering emulsions of water:octanol at varying aqueous pH values, using ionizable carboxyl polystyrene nanoparticles of 320 nm and 810 nm diameter. Remarkably we observe two emulsion phase inversions, one resulting from an increase in pH and a second due to an increase in particle size. To illuminate t...

We report methods to synthesize sub-micron and micron-sized patchy silica particles with fluorescently labeled hemispherical titania protrusions, as well as routes to efficiently characterize these particles and self-assemble these particles into non-close-packed structures. The synthesis methods expand upon earlier work in literature, in which sil...

Access to versatile and stable nanostructures formed by the self-assembly of block copolymers in water is essential for biomedical applications. These applications require control over the stability, morphology, and size of the formed nanostructures. Here, we study the self-assembly in water of a library of fully discrete and sequence-controlled AB...

Frost weathering of porous materials caused by seasonal temperature changes is a major source of damage to the world’s infrastructure and cultural heritage. Here we investigate poly(vinyl alcohol) (PVA) addition as a means to enhance the freeze-thaw durability of concrete without compromising its structural or mechanical integrity. We evaluate the...

Necessitated by the subzero temperatures and seasonal exposure to ice, various organisms have developed a remarkably effective means to survive the harsh climate of their natural habitats. Their ice-binding (glyco)proteins keep the nucleation and growth of ice crystals in check by recognizing and binding to specific ice crystal faces, which arrests...

Enzymes are widely employed to reduce the environmental impact of chemical industries as biocatalysts improve productivity and offer high selectively under mild reaction conditions in a diverse range of chemical transformations. The poor stability of biomacromolecules under reaction conditions is often a critical bottleneck to their application. Pr...

Due to their wide number of biological functions and potential applications, self-assembled nanotubes constitute highly relevant targets in noncovalent synthesis. Herein, we introduce a novel approach to produce supramolecular nanotubes with defined inner and outer diameters from rigid rod-like monomers programmed with complementary nucleobases thr...

Engineered living materials have the potential for wide-ranging applications such as biosensing and treatment of diseases. Programmable cells provide the functional basis for living materials, however, their release into the environment raises numerous biosafety concerns. Current designs that limit the release of genetically engineered cells typica...

Antifreeze (glyco)proteins (AF(G)Ps) have received increasing attention as potential cryopreservation agents since their discovery in the 1970s. While cryopreservation strategies for specific cells (such as red blood cells) are successful and widely implemented, preservation of other cell types, tissues and whole organs remains challenging. This is...

The assembly of oppositely charged block copolymers, containing small thermoresponsive moieties, was investigated as a function of salt concentration and temperature. Aqueous solutions of poly-[N-isopropylacrylamide]-b-poly[dimethylaminoethyl methacrylate] (NIPAM44-b-DMAEMA216) and PNIPAM-b-poly[acrylic acid]-b-PNIPAM (NIPAM35-b-AA200-b-NIPAM35) we...

We report the synthesis and self-assembly of a library of squaramide-based bolaamphiphiles with variable hydrophobic and hydrophilic domain sizes, consisting of varied aliphatic chains (n = 2 to 12 methylene repeat units) and linear oligo(ethylene glycol) (m = 11 to 36 repeat units), to understand their effect on the formation of supramolecular pol...

Gram-negative bacteria produce repeats-in-toxin adhesion proteins (RTX adhesins) to facilitate microbial adhesion. These large, multidomain proteins share a common architecture comprised of four regions. First to emerge from the bacterium, C terminal end leading, is the RTX export sequence that directs the protein through the type 1 secretion syste...

It has been hypothesized that the therapeutic effects of artepillin C, a natural compound derived from Brazilian green propolis, are likely related to its partition in the lipid bilayer component of biological membranes. To test this hypothesis, we investigated the effects of the major compound of green propolis, artepillin C, on model membranes (s...

Solid particles adsorbed at fluid interfaces are crucial for the mechanical stability of Pickering emulsions. The key parameter which determines the kinetic and thermodynamic properties of these colloids is the particle contact angle, θ. Several methods have recently been developed to measure the contact angle of individual particles adsorbed at li...

Ultrasound is the most commonly used clinical imaging modality. However, in applications requiring cell‐labeling, the large size and short active lifetime of ultrasound contrast agents limit their longitudinal use. Here, 100 nm radius, clinically applicable, polymeric nanoparticles containing a liquid perfluorocarbon, which enhance ultrasound contr...

Understanding the relations between the formation, structure, dynamics and functionality of complex synthetic materials is one of the great challenges in chemistry and nanotechnology and represents the foundation for the rational design of novel materials for a variety of applications. Initially conceived to study biology below the diffraction limi...

Stiffening due to internal stress generation is of paramount importance in living systems and is the foundation for many biomechanical processes. For example, cells stiffen their surrounding matrix by pulling on collagen and fibrin fibers. At the subcellular level, molecular motors prompt fluidization and actively stiffen the cytoskeleton by slidin...

The cytoskeleton is a highly adaptive network of filamentous proteins capable of stiffening under stress even as it dy-namically assembles and disassembles with time constants of minutes. Synthetic materials that combine reversibility and strain-stiffening properties remain elusive. Here, strain-stiffening hydrogels that have dynamic fibrous polyme...

In article number 1802089, Ilja K. Voets and co‐workers report on the temporally programmed, self‐regulating formation and dissociation of complex coacervate core micelles (C3Ms) comprising a double hydrophilic block copolymer and a pH‐responsive polyfluorene‐based conjugated polyelectrolyte as building blocks and a molecular sensor (doxorubicin HC...

Anfinsen's famous experiment showed that the restoration of catalytic activity of a completely unfolded ribonuclease A is only possible when the correct order of events is followed during the refolding process. Inspired by this work, the effect of structural constraints induced by covalent cross-links on the folding of a synthetic polymer chain via...

The synthesis of charged polymers often requires the polymerization of protected monomers, followed by a polymer-analogous reaction to the polyelectrolyte product. We present a mild, facile method to cleave tert-butyl groups from poly(tert-butyl acrylate) blocks that yields poly(acrylic acid) (pAA) blocks free of traces of the ester. The reaction u...

The supramolecular folding of amphiphilic heterograft copolymers equipped with dendritic pendants is investigated using a combination of proton nuclear magnetic resonance (¹H NMR) spectroscopy, small‐angle X‐ray scattering, and circular dichroism spectroscopy. Hereto, the linear poly(ethylene glycol) pendants normally used to convey water compatibi...

Self-consistent field (SCF) calculations and light scattering experiments were performed to study the pH and salt response of micelles composed of surfactants with a single weak acid group in aqueous salt solution. To this end, the common surfactant Brij 35 was oxidized to yield a polyoxyethylene alkyl ether carboxylic acid with a single terminal w...

In biology, polymorphism is a well-known phenomenon by which a discreet biomacromolecule can adopt multiple specific conformations in response to its environment. The controlled incorporating polymorphism into non-covalent aqueous assemblies of synthetic small molecules is an important step towards the development of bioinspired responsive material...

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 f...

Nucleic acid–polymer conjugates are an attractive class of materials endowed with tunable and responsive character. Herein, we exploit the dynamic character of nucleic acids in the preparation of hybrid DNA–covalent polymers with extendable grafts by the hybridization chain reaction. Addition of DNA hairpins to an initiator DNA–dextran graft copoly...

Supramolecular block copolymers are becoming attractive materials in nascent optoelectronic and catalytic technologies. However, their dynamic nature precludes the straightforward tuning and analysis of the polymer's structure. Here we report the elucidation on the microstructure of triarylamine triamide-based supramolecular block copolymers throug...

Despite the rapid development of complex functional supramolecular systems, visualization of these architectures under native conditions at high resolution has remained a challenging endeavor. Super-resolution microscopy was recently proposed as an effective tool to unveil one-dimensional nanoscale structures in aqueous media upon chemical function...

Repeats-In-Toxin (RTX) adhesins are present in many Gram-negative bacteria to facilitate biofilm formation. Previously, we reported that the 1.5-MDa RTX adhesin (MpIBP) from the Antarctic bacterium, Marinomonas primoryensis, is tethered to the bacterial cell surface via its N-terminal Region I (RI). Here, we show the detailed structural features of...

Synthetic hydrogel materials can recapitulate the natural cell microenvironment; however, it is equally necessary that the gels maintain cell viability and phenotype while permitting reisolation without stress, especially for use in the stem cell field. Here, we describe a family of synthetically accessible, squaramide-based tripodal supramolecular...

Charged food hydrocolloids provide structure and texture in manufactured foods by their organization and electrostatic interactions with other species and small ions. These electrostatic interactions depend on their actual charge density which cannot be predicted from pKa values of weakly charged monomers. In practice, this is circumvented by the u...

We report on a molecular dynamics study on the relation between the structure and the orientational (and hydrogen bond) dynamics of hydration water around the ocean pout AFP III anti-freeze protein. We find evidence for an increasing tetrahedral structure from the area opposite to the ice binding site (IBS) towards the protein IBS, with the stronge...

To tailor the properties of colloidal materials, precise control over the self-assembly of their constituents is a prerequisite. Here, we govern the assembly of silica particles by functionalization with supramolecular moieties which interact with each other via directional and reversible hydrogen bonding. Through a generally applicable synthesis p...

Complex coacervate core micelles (C3Ms) form upon complexation of oppositely charged copolymers. These co‐assembled structures are widely investigated as promising building blocks for encapsulation, nanoparticle synthesis, multimodal imaging, and coating technology. Here, the impact on ice growth is investigated of C3Ms containing poly(vinyl alcoho...

During the last decade, the synthesis and application of metal–organic framework (MOF) nanosheets has received growing interest, showing unique performances for different technological applications. Despite the potential of this type of nanolamellar materials, the synthetic routes developed so far are restricted to MOFs possessing layered structure...

The particle growth of silica below the isoelectric point plays a key role in oil well cements, production of silica gels and production of nano-silica by dissolving silicates. In this article, we study the particle growth of silica below the isoelectric point using olivine, a silicate mineral, and sodium silicate solutions as silica sources in aci...

Numerical self-consistent field (SCF) lattice computations allow a priori determination of the equilibrium morphology and size of supramolecular structures originating from the self-assembly of neutral block copolymers in selective solvents. The self-assembly behavior of poly(ethylene oxide)-block-poly-ε-caprolactone (PEO-PCL) block copolymers in w...

A family of amphiphilic, heterograft copolymers containing hydrophilic, hydrophobic, and supramolecular units based on Jeffamine M-1000, dodecylamine, and benzene-1,3,5-tricarboxamide (BTA) motifs, respectively, was prepared via a postfunctionalization approach. The folding of the copolymers in water into nanometer-sized particles was analyzed by a...

In article number 1701043, Albertus P. H. J. Schenning and co-workers, explore how photo-responsive small molecules can be monolithically aligned when exposed to linearly polarized light in thin films with sub-5 nm cylindrical nanopatterns, while when exposed to unpolarized light the self-assembled nanocylinders are aligned out-of-plane. These resu...

Bacterial adhesins are modular cell-surface proteins that mediate adherence to other cells, surfaces, and ligands. The Antarctic bacterium Marinomonas primoryensis uses a 1.5-MDa adhesin comprising over 130 domains to position it on ice at the top of the water column for better access to oxygen and nutrients. We have reconstructed this 0.6-μm-long...

Supplementary

While self-assembled molecular building blocks could lead to many next-generation functional organic nanomaterials, control over the thin-film morphologies to yield monolithic sub-5 nm patterns with 3D orientational control at macroscopic length scales remains a grand challenge. A series of photoresponsive hybrid oligo(dimethylsiloxane) liquid crys...

Cyclic peptides (CPs) that self-assemble in nanotubes can be candidates for use as anti-freeze proteins. Based on the cyclic peptide sequence cyclo-[(L-LYS-D-ALA- L-LEU-D-ALA)2], which can stack into nanotubes, we propose a putative anti-freeze cyclic peptide (AFCP) sequence, cyclo-[(L-LYS-D-ALA)2-(L-THR-D-ALA)2], contain- ing THR-ALA-THR ice bindi...

Ice-binding proteins (IBP) facilitate survival under extreme conditions in diverse life forms. IBPs in polar fishes block further growth of internalized environmental ice and inhibit ice recrystallization of accumulated internal crystals. Algae use IBPs to structure ice, while ice adhesion is critical for the Antarctic bacterium Marinomonas primory...

The color stability of dyes is crucial in commercial dyeing, whereas their use in scientific research often depends on color changes due to metachromasy. This is the result self-organization of dye molecules into a stacked organization onto a charged template, such as an oppositely charged polyelectrolyte. Literature shows that ‘reversal of metachr...