Nanocomposite materials are widespread in biological systems. Perhaps the most studied is the nacre of abalone shell, an orientated coating composed of alternating layers of aragonite (CaCO 3 ) and a biopolymer. Its laminated structure simultaneously provides strength, hardness and toughness: containing about 1 vol. % polymer, nacre is twice as hard and 1,000 times as tough as its constituent phases 1 . Such remarkable properties have inspired chemists and materials scientists to develop synthetic, 'biomimetic' nanocomposite assemblies 2-5 . Nonetheless, the efficient processing of layered organic-inorganic composites remains an elusive goal. Here we report a rapid, efficient selfassembly process for preparing nanolaminated coatings that mimic the structure of nacre. Beginning with a solution of silica, surfactant and organic monomers, we rely on evaporation during dip-coating to induce the formation of micelles and partitioning of the organic constituents into the micellar interiors 6 . Subsequent self-assembly of the silica-surfactant-monomer micellar species into lyotropic mesophases 7 simultaneously organizes the organic and inorganic precursors into the desired nanolaminated form. Polymerization fixes this structure, completing the nanocomposite assembly process. This approach may be generalized both to other composite architectures and to other materials combinations.Natural nanocomposites are formed by biomineralization 5 , a templated self-assembly process in which pre-organized organic surfaces regulate the nucleation, growth, morphology and orientation of inorganic crystals. Related synthetic, so-called 'biomimetic', approaches include crystallization beneath Langmuir monolayers 8 , crystallization on self-assembled monolayers 3,9 , supramolecular self-assembly 2,6,10 and sequential deposition 11 . Of these, only the last two offer the ability to introduce periodic microstructural and compositional changes needed for nanocomposite assembly. With regard to nanolaminated structures, supramolecular self-assembly has resulted in the formation of lamellar (silica/surfactant) films 12 or letters to nature 256

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Mucosal coupling with traction generated by interaction of migrating opposing surfaces provides the first comprehensive theory that explains the observed characteristics of primary acquired cholesteatoma. The somewhat counterintuitive hypothesis that cholesteatoma is fundamentally a mucosal disease has numerous therapeutic implications.

Despite recent advancements in cancer immunotherapy, accurate monitoring of its efficacy is challenging due to heterogeneous immune responses. Conventional imaging techniques lack the sensitivity and specificity for early response assessment. In this study, we designed a granzyme B (GrB) nanoreporter (GNR) that can deliver an immune checkpoint inhibitor to the tumor and track time-sensitive GrB activity as a direct way to monitor initiation of effective immune responses. Anti–programmed death-ligand 1 (PD-L1) antibody–conjugated GNRs inhibited PD-1/PD-L1 interactions efficiently and induced T cell–mediated GrB release that can be imaged using activatable imaging probe. GNRs enabled real-time immunotherapy response monitoring in a tumor-bearing mice model and distinguished between highly responsive and poorly responsive tumors. Furthermore, increasing doses resulted in a better response and enhanced sensitivity in poorly responsive tumors. These findings indicate that GNR has the potential to serve as a tool for sensitive and noninvasive evaluation of immunotherapy efficacy.

The preparation and characterization of coatings made from polydiacetylene colloids on nano- and microporous membranes and their potential for the detection of microorganisms are presented.

This study aims to enhance the mechanical properties, thermal stability, weathering resistance and antibacterial property of a styrene acrylic polyurethane coating by adding rutile titania dioxide (R-TiO2) nanoparticles in coating formulation. The styrene acrylic polyurethane/R-TiO2 nanocomposite had been prepared by using ultrasonication. The effects of nanoparticles on the mechanical properties, thermal stability and weathering resistance of as-prepared coatings were investigated by using the adhesion strength and ball impact tests, the Fourier transform infrared and UV–vis analyses, thermogravimetric analysis (TGA), and UV/condensation weathering chamber equipped with UVA-340 fluorescent lamps, respectively. The disperse quality of nanoparticles in the coating was examined by using the field emission scanning electron microscope (FESEM). The mechanical test results showed that suitable content of R-TiO2 nanoparticles in the nanocomposite coating was 2 wt%. The FESEM images indicated that the nanoparticles were dispersed homogeneously into the entire volume of the coating. For the nanocomposite prepared by 3 h of ultrasonication, the average size of nanoparticles was in range of 40–50 nm. The ball impact and adhesion tests showed that the incorporation of nanoparticles into the coating significantly enhanced the impact strength from 120 to 145 kg cm and increased the adhesion from level 1 to level 0. The TGA test illustrated that in presence of nanoparticles, the decomposition temperature of coating increased from 146.9 °C to 154.21 °C. For the temperature at 50% loss in mass (T50%), it was found that the T50% of the neat coating is 351.86 °C. Adding the 2 wt% R-TiO2 nanoparticles into coating increased the T50% value to 360.06 °C. After UV/condensation accelerated weathering test (30 cycles), the significant improvement in weight loss, impact strength and adhesion of the neat coating was observed with the presence of nanoparticles. The antibacterial test showed that in the nanocomposite coating, R-TiO2 nanoparticles exhibited their photocatalytic effect in the inhibition against E. coli bacterial growth. Incorporating 2 wt% of R-TiO2 nanoparticles into the coating reduced the bacterial concentration by 6.1% after 60 min of culture.

Azide–alkyne “click” cyclization was used to prepare a series of polymerizable acetoacetate monomers containing a 1,2,3-trizolium ionic liquid group. The monomers were subsequently polymerized using base-catalyzed Michael addition chemistry, producing a series of covalently crosslinked 1,2,3-triazolium poly(ionic liquid) (TPIL) networks. Structure–activity relationships were conducted to gauge how synthetic variables, such as counteranion ([Br], [NO 3 ], [BF 4 ], [OTf], and [NTf 2 ]), and crosslink density (acrylate/acetoacetate ratio) effected thermal, mechanical, and conductive properties. TPIL networks were found to exhibit ionic conductivities in the range of 10 –6 –10 –9 S/cm (30 °C, 30% relative humidity), as determined from dielectric relaxation spectroscopy, despite their highly crosslinked nature. Temperature-dependent conductivities demonstrate a dependence on polymer glass transition, with free-ion concentrations impacted by various ions’ Lewis acidity/basicity and ion mobilities impacted by freely mobile anion size.

Lipid-based phagocytosis nanoenhancer concurrently inhibit CD47-SIRPα signaling pathway, increase cellular interactions between macrophages and cancer cells, and enhance macrophage immunotherapy.