Pure protein bilayers and vesicles are formed using the native, fungal hydrophobin HFBI. Bilayers with hydrophobic (red) and hydrophilic (blue) core are produced and, depending on the type of core, vesicles in water, oily media, and even in air can be created using microfluidic jetting. Vesicles in water are even able to incorporate functional gramicidin A pores.

They are classically prepared using exfoliation, exploiting promoted intralayer bonding over weak interlayer interactions of their 3D counterparts. [4] The exfoliation of graphene [1] has triggered searches for other covalently interconnected atomically thin 2D nanomaterials, such as transition metal dichalcogenides, [5] Mxenes, [6] boron nitrides, [7] and clays, [8] based on exfoliation and delamination, [9] molecular beam epitaxy, [10] and advanced synthesis. [11] In ultrathin 2D nanomaterials, the quantum confinement of electrons in two dimensions opens novel applications, e.g., in flexible optoelectronic devices. [4,12,13] Beyond atomic and molecular-level networks, a less studied approach deals with the selfassembly of metal nanoparticles (NPs) to form 2D monolayer membranes, i.e., of nanometric thickness. That this could be relevant, is suggested by the tunable optoelectronic and mechanical properties of self-assembled 2D materials of narrow size dispersed plasmonic NPs. [14][15][16][17] However, metal NPs classically suffer from uncontrolled aggregation tendency, polydispersity, and lack of directional interactions. [18][19][20][21] Additionally, nonspecific bindings and slow diffusion of colloidal-level 2D nanomaterials have provided an extraordinary palette of mechanical, electrical, optical, and catalytic properties. Ultrathin 2D nanomaterials are classically produced via exfoliation, delamination, deposition, or advanced synthesis methods using a handful of starting materials. Thus, there is a need to explore more generic avenues to expand the feasibility to the next generation 2D materials beyond atomic and molecular-level covalent networks. In this context, self-assembly of atomically precise noble nanoclusters can, in principle, suggest modular approaches for new generation 2D materials, provided that the ligand engineering allows symmetry breaking and directional internanoparticle interactions. Here the self-assembly of silver nanoclusters (NCs) capped with p-mercaptobenzoic acid ligands (Na 4 Ag 44 -pMBA 30 ) into large-area freestanding membranes by trapping the NCs in a transient solvent layer at air-solvent interfaces is demonstrated. The patchy distribution of ligand bundles facilitates symmetry breaking and preferential intralayer hydrogen bondings resulting in strong and elastic membranes. The membranes with Young's modulus of 14.5 ± 0.2 GPa can readily be transferred to different substrates. The assemblies allow detection of Raman active antibiotic molecules with high reproducibility without any need for substrate pretreatment.

In this study, the interaction forces between different cellulosic nanomaterials and a protein domain belonging to cellulose binding modules family 1 (CBM1) were investigated at the molecular scale. Cellulose binding modules are protein domains found in carbohydrate active enzymes having an affinity toward cellulosic materials. Here, the binding force of a fusion protein containing a cellulose binding module (CBM1) produced recombinantly in E. coli was quantified on different cellulose nanocrystals immobilized on surfaces. Adhesion of the CBM on cellulose with different degrees of crystallinity as well as on chitin nanocrystals was examined. This study was carried out by single molecule force spectroscopy using an atomic force microscope, which enables the detection of binding force of individual molecules. The study contains a preliminary quantification of the interactions at the molecular level that sheds light on the development of new nanocellulose-based nanocomposites with improved strength and elasticity.

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