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Abstract: Measuring live cells by FTIR spectroscopy is challenging due to their small size and the absorbance of water in the mid-IR region. However, measuring cells in their live state is important to observe changes in the biological processes of cells that are unaffected by fixation and drying processes. Recently, ZnS hemispheres were used to sandwich live cells in a 6 µm layer of cell medium, which simultaneously limit the absorbance of water and increase the spatial resolution by x2.25, thereby enabling high quality spectra to be acquired from living cells. So far, this method has been used as an imaging technique to showcase the distribution of biomolecules within a single cell. In this work, we present an alternative use of these ZnS hemispheres as a high throughput screening tool. We obtained high quality spectra of a single cell at a measurement rate of ∼1 min/cell. We’ve applied this technique to observe the biochemical effects of various polystyrene microplastics on two mammalian cell lines (J774A.1 and A549), however the method can easily be expanded to other cell lines, microplastics, and alternative xenobiotics.

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Abstract: Triboelectric nanogenerators (TENGs), which convert mechanical energy into electrical signals, have emerged as apromising platform for self-powered motion sensing. However, the development of high-sensitivity TENG sensors remains limited by the availability of tunable and efficient tribo-positive materials, which are electron donors. In this work, we present a material design strategy based on the incorporation of electron-donating functionalized metal–organic framework (MOF) fillers into a polyurethane (PU) polymer matrix. Three functional groups (−CH3, −NH2, and −OH) were systematically studied to investigate their influence on triboelectric performance. The resulting composite membranes demonstrated tunable charge-donating behavior and improved electrical output, with the −OH-modified MOF yielding the highest electrical output of 197.6 ± 1.3 V and 0.47 ± 0.08 μA/cm2, which are 2.3 and 3.2 times higher than that of the pristine PU. The enhanced charge-donating mechanism was elucidated through a combination of advanced micro- and nanoscale chemical and mechanical analysis. Theoretical calculations employing ab initio density functional theory (DFT) were performed to reveal the electron distribution within the periodic MOF structure. Furthermore, the practical application of the optimized TENG device was demonstrated in a single-electrode shear sensor configuration, exhibiting high sensitivity in sliding motion detection. This study highlights a scalable and biocompatible strategy for improving tribo-positive materials and advancing the performance of tunable TENG-based sensors to enable shear force monitoring.

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Abstract: A facile approach is demonstrated for synthesizing a mechanically tough ZIF-71 [Zn(dcIm)2; dcIm = 4,5-dichloroimidazole] monoliths with a polymer binder, employing namely poly-methyl methacrylate (PMMA) through a sol-gel process. The addition of a slight polymer binder (∼10 wt.%) to the sol-gel mixture is shown to enhance the mechanical properties such as the elastic modulus, hardness, fracture toughness, strain hardening, and creep behavior of the composite monoliths compared to the pure ZIF-71 monoliths. Nitrogen sorption measurements revealed that the composite monoliths have a high surface area (∼350 m2/g) although it was reduced from ∼600 m2/g due to pore blockage by the polymer. Composite monoliths exhibit less surface cracks and are relatively stiffer but are notably tougher than the pure ZIF-71 monoliths as the fracture toughness tripled from around 0.15 MPa m1/2 to around 0.45 MPa m1/2. Despite the incorporation of a small quantity of polymer in the monolith, this has a significant impact on increasing the mechanical stiffness, hardness and fracture resistance of the resulting monoliths. Creep response observed under a constant load revealed the presence of PMMA incorporated in the composite monolith. Nearfield infrared (IR) nanospectroscopy via nanoFTIR and pseudoheterodyne (PsHet) scattering-Scanning Nearfield Optical Microscopy (s-SNOM) IR imaging on plastically deformed and indented surfaces revealed local chemical structure-mechanical interactions. Our findings suggest that the polymer chains are trapped inside the ZIF-71 structure, thereby improving the mechanical resilience that might pave the way to future scaling up of MOF monoliths for practical applications and durable devices.

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Abstract: The empty, extensive low-density lattice topology of hemoglycin is examined to understand how in space, and possibly as early as 800 Myr into cosmic time a rod-like polymer of glycine and iron came into dominance. A central question to be answered is whether the hemoglycin rod lattice with diamond 2H symmetry represents the most efficient covering of space by a regular arrangement of identical rods. Starting from the tetrahedral symmetry of every hemoglycin lattice vertex we find that the regular truncated tetrahedron of Archimedes may be expanded until neighbouring hexagon faces are coincident, at which point space filling is 23/24 or 95.8333 per cent complete. We describe the unit cells of the diamond 2H rod lattice and its conforming near-complete space-filling structure, which has identical symmetry. Maximum space filling via a minimum of molecular material can allow hemoglycin to drive accretion in molecular clouds, contributing to the composition of dust, and providing a background for its widespread presence in meteoritic samples and in cometary material that falls to Earth. The optical properties of hemoglycin lattice entities are derived from quantum calculations of ultraviolet (UV) and visible transition energies and strengths. The hemoglycin extinction curve duplicates the nominal 218 nm UV absorption feature known as the UV bump, together with two visible absorption features present in a generic compilation of astronomical extinction data.

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Abstract: Liquid biopsy is revolutionizing cancer management, with circulating tumor cells (CTCs), offering a transformative approach to screening, diagnosis, and treatment monitoring. However, existing CTC isolation methods relying on antigen expression or physical properties lack robustness, are operator-dependent, and suffer from automation challenges, leading to inconsistent and time-intensive analyses. A universal, unbiased methodology for CTC detection across tumor types is critically needed. Here, we present the first proof-of-concept study demonstrating the use of Fourier transform infrared (FT-IR) microspectroscopy to study cytospun blood samples coupled with a random forest (RF) classifier, for the detection of a single CTC in the blood of a lung cancer patient as confirmed via immunohistochemistry. Notably, our method utilizes glass coverslips as substrates, routinely employed in pathology departments, enabling seamless integration with histopathological analyses (e.g., staining, immunohistochemistry). Using FT-IR spectral data from in vitro growing lung cancer cells as a training model, we achieved precise CTC identification based on biochemical composition, specifically within the Fingerprint region (1800 cm–1 to 1350 cm–1). This study introduces FT-IR microspectroscopy as a novel, label-free approach for CTCs detection in liquid biopsies, with the potential to redefine cancer diagnostics. By enhancing precision and accessibility in CTC identification, the clinical implementation of this methodology may represent a significant advancement in personalized oncology, offering a clinically viable tool for real-time cancer monitoring and improved patient stratification.