X-ray detectors are broadly utilized in medical imaging and product inspection. Halide perovskites recently demonstrate excellent performance for direct X-ray detection. However, ionic migration causes large noise and baseline drift, limiting the detection and imaging performance. Here we largely eliminate the ionic migration in cesium silver bismuth bromide (Cs 2 AgBiBr 6 ) polycrystalline wafers by introducing bismuth oxybromide (BiOBr) as heteroepitaxial passivation layers. Good lattice match between BiOBr and Cs 2 AgBiBr 6 enables complete defect passivation and suppressed ionic migration. The detector hence achieves outstanding balanced performance with a signal drifting one order of magnitude lower than all previous studies, low noise (1/ f noise free), a high sensitivity of 250 µC Gy air −1 cm –2 , and a spatial resolution of 4.9 lp mm −1 . The wafer area could be easily scaled up by the isostatic-pressing method, together with the heteroepitaxial passivation, strengthens the competitiveness of Cs 2 AgBiBr 6 -based X-ray detectors as next-generation X-ray imaging flat panels.

This study reports a family of photothermal materials, metal ion/tannic acid assemblies (MITAs). MITAs from Fe, V, and Ru afford excellent photothermal efficiency (η ≈ 40%). Sharply differing from the currently existing photothermal agents, MITAs are highlighted by merits including green synthesis, facile incorporation of diagnostic metal ions, and particularly topology-independent adhesion. Owing to the adhesion nature of MITAs, various kinds of MITA-based nanoengineerings are readily available via the self-adhesion of MITAs onto diverse templates, enabling MITAs well suited as a photothermal platform for versatile combination with other therapy approaches and imaging techniques. As a proof of concept, polymeric/inorganic nanoparticle/nanovesicle-supported Fe-tannic acid (FeTA) is fabricated. The photothermal effect is shown to be unaffected by the template origin and type and FeTA thickness on the templates. We validate the potency of nanovesicle-supported FeTA (PNV@FeTA) for tumor-specific photoactivated utilizations, including NIR photothermal therapy with complete tumor elimination, photothermal imaging (PTI), and photoacoustic imaging (PAI) in addition to T-MRI imaging. PNV@FeTA can be simultaneously equipped with functionalities, including T-MRI imaging by additionally doping Mn and NIR fluorescence imaging by encapsulating a hydrophilic NIR fluoroprobe. MITA demonstrates unparalleled superiority as a photothermal platform in engineering multimodal theranostics for advanced applications.

Lantipeptides are ribosomally synthesized and posttranslationally modified peptides containing thioether cross-links. We describe the preparation of seven different lantipeptides in Escherichia coli and demonstrate that this methodology can be used to incorporate nonproteinogenic amino acids.

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Understanding amazingly complex brain functions and pathologies requires a complete cerebral vascular atlas in stereotaxic coordinates. Making a precise atlas for cerebral arteries and veins has been a century-old objective in neuroscience and neuropathology. Using micro-optical sectioning tomography (MOST) with a modified Nissl staining method, we acquired five mouse brain data sets containing arteries, veins, and microvessels. Based on the brain-wide vascular spatial structures and brain regions indicated by cytoarchitecture in one and the same mouse brain, we reconstructed and annotated the vascular system atlas of both arteries and veins of the whole mouse brain for the first time. The distributing patterns of the vascular system within the brain regions were acquired and our results show that the patterns of individual vessels are different from each other. Reconstruction and statistical analysis of the microvascular network, including derivation of quantitative vascular densities, indicate significant differences mainly in vessels with diameters less than 8 μm and large than 20 μm across different brain regions. Our precise cerebral vascular atlas provides an important resource and approach for quantitative studies of brain functions and diseases.

Food-grade colloidal particles and complexes, which are formed via modulation of the noncovalent interactions between macromolecules and natural small molecules, can be developed as novel functional ingredients in a safe and sustainable way. For this study was prepared a novel zein/tannic acid (TA) complex colloidal particle (ZTP) based on the hydrogen-bonding interaction between zein and TA in aqueous ethanol solution by using a simple antisolvent approach. Pickering emulsion gels with high oil volume fraction (φ(oil) > 50%) were successfully fabricated via one-step homogenization. Circular dichroism (CD) and small-angle X-ray scattering (SAXS) measurements, which were used to characterize the structure of zein/TA complexes in ethanol solution, clearly showed that TA binding generated a conformational change of zein without altering their supramolecular structure at pH 5.0 and intermediate TA concentrations. Consequently, the resultant ZTP had tuned near neutral wettability (θ(ow) ∼ 86°) and enhanced interfacial reactivity, but without significantly decreased surface charge. These allowed the ZTP to stabilize the oil droplets and further triggered cross-linking to form a continuous network among and around the oil droplets and protein particles, leading to the formation of stable Pickering emulsion gels. Layer-by-layer (LbL) interfacial architecture on the oil-water surface of the droplets was observed, which implied a possibility to fabricate hierarchical interface microstructure via modulation of the noncovalent interaction between hydrophobic protein and natural polyphenol.

We report the novel use of the naturally occurring saponin, glycyrrhizic acid (GA) as a structuring material to transform liquid oil into a soft-solid structured emulsion system. The GA nanofibrils from the anisotropic self-assembly of GA molecules were first used as stabilizers to fabricate olive oil-in-water emulsions using a facile one-step emulsification at high temperature. Then, the obtained emulsions were further self-organized into the emulsion gel by applying a subsequent cooling to trigger the gel network formation, which is mostly due to the enhanced noncovalent interactions among GA fibrils in the continuous phase as well as at the droplet surface. The GA fibrils could adsorb at the interface in a multilayer form, leading to the formation of unique fibril shells with high electrostatic repulsive force, which could provide superior stability for the GA fibril-stabilized oil droplets and thus the whole emulsion gel during storage and heating. The thermoreversible gel-sol transitions of a self-assembled GA fibrillar network in the continuous phase endow the stable emulsion gels with a temperature-responsive switchable behavior. Moreover, the GA fibril-coated oil droplets embedded in the network were found to be closely packed together and connected with the gel matrix. As a consequence, the emulsion gels exhibited many interesting rheological behaviors, including a high gel strength, shear sensitivity, and good thixotropic recovery. These simple and inexpensive smart responsive oil structuring materials based on natural saponins could find novel applications in the fields of food, pharmaceuticals, or cosmetics.

Lipid peroxidation in oil-in-water (o/w) emulsions leads to rancidity and carcinogen formation. This work attempted to protect lipid droplets of emulsions from peroxidation via manipulation of the emulsions' interface framework using dual-function zein/CH complex particles (ZCPs). ZCP with intermediate wettability was fabricated via a simple antisolvent approach. Pickering emulsions were produced via a simple and inexpensive shear-induced emulsification technique. ZCP was irreversibly anchored at the oil-water interface to form particle-based network architecture therein, producing ultrastable o/w Pickering emulsions (ZCPEs). ZCPE was not labile to lipid oxidation, evidenced by low lipid hydroperoxides and malondialdehyde levels in the emulsions after thermally accelerated storage. The targeted accumulation of curcumin, a model antioxidant, at the interface was achieved using the ZCP as interfacial vehicle, forming antioxidant shells around dispersed droplets. The oxidative stability of ZCPEs was further improved. Interestingly, no detectable hexanal peak appeared in headspace gas chromatography of the Pickering emulsions. The novel interfacial architecture via the combination of steric hindrance from ZCP-based membrane and interfacial cargo of curcumin endowed the emulsions with favorable oxidative stability. This study opens a promising pathway for producing antioxidant emulsions via the combination of Pickering stabilization mechanism and interfacial delivery of antioxidant.