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Bitterness elicits unpleasant sensations in humans, which can hinder the acceptance of foods and medication adherence. Therefore, identifying and masking bitter tastes is crucial for developing palatable foods and promoting medication compliance in the food and pharmaceutical industries. To achieve this, employing agonism and antagonism of bitter taste receptors as effective strategies at the molecular level is essential. In this study, a bioelectronic tongue is developed to characterize the agonism and antagonism of bitter taste receptors. The human bitter taste receptors hTAS2R16 and hTAS2R31 are produced using an Escherichia coli expression system and reconstituted into nanodiscs (NDs). Subsequently, hTAS2R16‐ and hTAS2R31‐NDs are immobilized on the surface of graphene field‐effect transistors (FETs) to construct bioelectronic tongues. The developed system sensitively detected the bitter agonists, salicin and saccharin, at concentrations as low as 100 fM, with high selectivity in real‐time. The dose‐dependent curves shifted and K values decreased by the antagonists of hTAS2R16 and hTAS2R31, indicating antagonism‐based masking of bitter taste. Therefore, the developed bioelectronic tongue holds promise for identifying bitter tastes and evaluating the masking of bitterness based on the agonism and antagonism of hTAS2Rs. [ABSTRACT FROM AUTHOR]

Cellular membranes have long served as an inspiration for nanomaterial research. The preparation of ultrathin polydopamine (PDA) films with integrated protein pores containing phospholipids and an embedded domain of a membrane protein glycophorin A as simplified cell membrane mimics is reported. Large area, ultrathin PDA films are obtained by electropolymerization on gold surfaces with 10–18 nm thickness and dimensions of up to 2.5 cm2. The films are transferred from gold to various other substrates such as nylon mesh, silicon, or substrates containing holes in the micrometer range, and they remain intact even after transfer. The novel transfer technique gives access to freestanding PDA films that remain stable even at the air interfaces with elastic moduli of ≈6–12 GPa, which are higher than any other PDA films reported before. As the PDA film thickness is within the range of cellular membranes, monodisperse protein nanopores, so‐called "nanodiscs," are integrated as functional entities. These nanodisc‐containing PDA films can serve as semi‐permeable films, in which the embedded pores control material transport. In the future, these simplified cell membrane mimics may offer structural investigations of the embedded membrane proteins to receive an improved understanding of protein‐mediated transport processes in cellular membranes. [ABSTRACT FROM AUTHOR]

In an attempt to manipulate the biological features of nanomaterials via both anisotropic shape and ligand modification, four types of nanoparticulates with good morphological stability are designed and engineered, including hybrid nanospheres, nanodiscs, and nanodiscs with edge modification or plane modification of octa-arginine (R8) sequence. It is found that the R8 modification anisotropy can trigger huge differences in the endocytosis, intracellular trafficking, and even tissue penetration of nanoparticulates. From plane modification to edge modification of R8, the maximum increase in cell uptake is up to 17-fold, which is much more significant than shape anisotropy alone. On the other hand, six types of different cell lines are investigated to simulate biological microenvironment. It is demonstrated that the maximum difference in cell uptake among six cell lines is 12-fold. Three main driving forces are found to contribute to such bio-nano interactions. Based on the findings of this study, it seems possible to manipulate the biointeraction mode of nanomaterials and its output by regulating their anisotropy in both shape and ligand modification. [ABSTRACT FROM AUTHOR]

There is a strong demand for techniques that allow the fabrication of biocompatible porous nanoparticles for drug delivery applications. In this work, a new method to fabricate size- and shape-controlled porous silicon (pSi) nanodiscs is described. The process relies on a combination of colloidal lithography and metal-assisted chemical etching. Height and diameter of the pSi nanodiscs can be easily adjusted. The nanodiscs are degradable in physiological milieu and are nontoxic to mammalian cells. In order to highlight the potential of the pSi nanodiscs in drug delivery, an in vitro investigation that involved loading of nanodiscs with the anticancer agent camptothecin and functionalization of the nanodisc periphery with an antibody that targets receptors on the surface of neuroblastoma cells is carried out. The thus-prepared nanocarriers are found to selectively attach to and kill cancer cells. [ABSTRACT FROM AUTHOR]

A two-step chemical approach to synthesize high quality Fe3O4 nanodisc is reported. The magnetic hyperthermia properties of the nanodisc and isotropic nanoparticles are investigated systematically. The results suggest that the nanodisc shows much higher specific absorption rate (SAR) than isotropic nanoparticles. This is attributed to the parallel alignment of nanodisc with respect to the alternating current magnetic field, which is confirmed by good agreement between experimental results and micromagnetic simulation. It is found that such parallel alignment could enhance the SAR value by a factor of ≈2 with respect to the randomly oriented case. The above results indicate that the nanodisc provides an excellent thermal seed for magnetic hyperthermia. This study sheds the light on the magnetic hyperthermia mechanism of magnetic nanodisc and it also opens the window to explore high efficiency thermal seeds by controlling the orientation of magnetic nanostructures. [ABSTRACT FROM AUTHOR]

In article number 1800846, Hiroshi Yabu, Guillaume Delaittre, and co‐workers propose a simple procedure to prepare nanoparticles with surface‐expressed reactive patches and corresponding nanodiscs by a nanoprecipitation technique with functional block copolymers. The surface pattern formation is controlled by the preparation conditions. Spatially confined functionalization is demonstrated by grafting model thiol compounds. These nanomaterials are structurally approaching biological particles and are interesting building blocks for colloidal assemblies. [ABSTRACT FROM AUTHOR]

Nanoparticles with structural or chemical anisotropy are promising materials in domains as diverse as cellular delivery, photonic materials, or interfacial engineering. The surface chemistry may play a major role in some of these contexts. Introducing reactivity into such polymeric nanomaterials is thus of great potential, yet is still a concept in its infancy. In the current contribution, a simple nanoprecipitation technique leads to nanoparticles with diameters as low as 150 nm and well‐defined reactive surface patches of less than 30 nm in width, as well as surface‐reactive flat, disc‐like nanoparticles with corresponding dimensions, via an additional crosslinking/delamination sequence. To this aim, chemically doped block copolymers (BCPs) are employed. Control over morphology is attained by tuning preparation conditions, such as polymer concentration, solvent mixture composition, and blending with non‐functional BCP. Surface reactivity is demonstrated using a modular ligation method for the site‐selective immobilization of thiol molecules. The current approach constitutes a straightforward methodology requiring minimal engineering to produce nanoparticles with confined surface reactivity and/or shape anisotropy. Nanoparticles with surface‐expressed reactive patches and corresponding nanodiscs are prepared by a simple nanoprecipitation technique with functional block copolymers. The surface pattern formation is controlled by preparation conditions (concentration, solvent, and functionality). Spatially confined functionalization is demonstrated by grafting model thiol compounds. These nanomaterials are structurally approaching biological particles and are interesting building blocks for colloidal assemblies. [ABSTRACT FROM AUTHOR]

Anisotropic modification on nanodiscs could trigger huge differences in their endocytosis mode and following behaviors. In article number 1700406 Zhifei Dai, Qiang Zhang, and co‐workers design analyze the cellular uptake of nanoparticulates differing in anisotropy of shape and ligand modification. This anisotropy‐based approach is promising for manipulating the biointeraction mode of nanomaterials and its outcome. [ABSTRACT FROM AUTHOR]