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The in vitro recapitulation of tumor microenvironment is of great interest to preclinical screening of drugs. Compared with culture of cell lines, tumor organ slices can better preserve the complex tumor architecture and phenotypic activity of native cells, but are limited by their exposure to fluid shear and gradual degradation under perfusion culture. Here, we established a decellularized liver matrix (DLM)–GelMA "sandwich" structure and a perfusion-based microfluidic platform to support long-term culture of tumor slices with excellent structural integrity and cell viability over 7 days. The DLM–GelMA was able to secrete cytokines and growth factors while providing shear protection to the tumor slice via the sandwich structure, leading to the preservation of the tumor microenvironment where immune cells (CD3, CD8, CD68), tumor-associated fibroblasts (α-SMA), and extracellular matrix components (collagen I, fibronectin) were well maintained. Furthermore, this chip presented anti-tumor efficacy at cisplatin (20 μM) on tumor patients, demonstrating our platform's efficacy to design patient-specific treatment regimens. Taken together, the successful development of this DLM–GelMA sandwich structure on the chip could faithfully reflect the tumor microenvironment and immune response, accelerating the screening process of drug molecules and providing insights for practical medicine. [ABSTRACT FROM AUTHOR]

Electrically responsive photonic crystals (ERPCs), a kind of electrophoretic color display material with significant market potential, feature a simple preparation process and allow for voltage-adjustable color transformation. However, their excessive electrical response time and limited color chromaticity have hindered their practical applications. In this context, this study presents a straightforward method to create ERPC devices based on SiO2/sodium dodecyl benzene sulfonate (SDBS)/acidified carbon nanotubes (ACNTs), which can switch color states reversibly with electric field application. During this process, the anion groups provided by SDBS are introduced into the slipping layer of microspheres resulting in high surface charges for colloidal particles, while the black material ACNTs enhance electronic ink coloring by absorbing incoherent scattered light. The high surface charge further improves the response rate and enhances stability and reversibility. Compared to previously reported ERPCs, the SiO2/SDBS/ACNT-based ERPC exhibits a shorter response time and higher chromaticity, laying a foundation for reflective displays. [ABSTRACT FROM AUTHOR]

Although renal fibrosis can advance chronic kidney disease and progressively lead to end-stage renal failure, no effective anti-fibrotic drugs have been clinically approved. To aid drug development, we developed a biomimetic renal fibrosis progression model on-chip to evaluate anti-fibrotic effects of natural killer cell-derived extracellular vesicles and pirfenidone (PFD) across different fibrotic stages. First, the dynamic interplay between fibroblasts and kidney-derived extracellular matrix (ECM) resembling the fibrogenic niche on-chip demonstrated that myofibroblasts induced by stiff ECM in 3 days were reversed to fibroblasts by switching to soft ECM, which was within 2, but not 7 days. Second, PFD significantly down-regulated the expression of α-SMA in NRK-49F in medium ECM, as opposed to stiff ECM. Third, a study in rats showed that early administration of PFD significantly inhibited renal fibrosis in terms of the expression levels of α-SMA and YAP. Taken together, both on-chip and animal models indicate the importance of early anti-fibrotic intervention for checking the progression of renal fibrosis. Therefore, this renal fibrosis progression on-chip with a feature of recapitulating dynamic biochemical and biophysical cues can be readily used to assess anti-fibrotic candidates and to explore the tipping point when the fibrotic fate can be rescued for better medical intervention. [ABSTRACT FROM AUTHOR]

Using the high incompatibility between the neutral stabilizer body and the block polyelectrolyte to drive phase separation during polymerization-induced self-assembly, a modular approach to systematically adjust ionic monomer/polymer solubility was developed to effectively identify monomers suitable for RAFT aqueous dispersion polymerization, with strong phase separation ability to form worm phases over a wide range of compositions and even at very low solid content. The block copolymer PMPS-MPS-P([META+][PF6−]), prepared by this method, acts as a "nano bridge" and achieves Ni loading on TiO2 with the help of the sol–gel method + thermal reduction. The atomic loading of Ni on TiO2 is achieved through strong covalent bonding, metallic bonding and the natural physical intertwining effect of the silane coupling agent. Interestingly, it was unexpectedly found that the TiC stable structure generated by this process, the ionization of part of the block polyelectrolyte after the thermal reduction treatment at 773 K and the loading process of Ni all can promote the formation of oxygen vacancy Ov, which facilitates the charge transfer and hydrogen precipitation reaction. It has superior photocatalytic ability and cheaper cost compared to the conventional impregnation dispersion method. These findings provide a new idea to modify the manipulated photocatalysts by defect engineering to achieve efficient photocatalytic efficiency and capability. [ABSTRACT FROM AUTHOR]

The certified power conversion efficiency (PCE) record of colloidal quantum dot solar cells (QDSCs) has considerably improved from below 4% to 16.6% in the last few years. However, the record PCE value of QDSCs is still substantially lower than the theoretical efficiency. So far, there have been several reviews on recent and significant achievements in QDSCs, but reviews on photoexcited carrier dynamics in QDSCs are scarce. The photovoltaic performances of QDSCs are still limited by the photovoltage, photocurrent and fill factor that are mainly determined by the photoexcited carrier dynamics, including carrier (or exciton) generation, carrier extraction or transfer, and the carrier recombination process, in the devices. In this review, the photoexcited carrier dynamics in the whole QDSCs, originating from individual quantum dots (QDs) to the entire device as well as the characterization methods used for analyzing the photoexcited carrier dynamics are summarized and discussed. The recent research including photoexcited multiple exciton generation (MEG), hot electron extraction, and carrier transfer between adjacent QDs, as well as carrier injection and recombination at each interface of QDSCs are discussed in detail herein. The influence of photoexcited carrier dynamics on the physiochemical properties of QDs and photovoltaic performances of QDSC devices is also discussed. [ABSTRACT FROM AUTHOR]

Retraction of 'Synthesis of atomic form nickel co-catalysts on TiO2 for improved photocatalysis via the RAFT technique' by Bo Zhang et al., New J. Chem., 2022, 46, 14239–14250, https://doi.org/10.1039/D2NJ02069F. [ABSTRACT FROM AUTHOR]

The design of efficient mixed Mn–Co oxides as oxygen reduction reaction (ORR) electrocatalysts in alkaline media has been boosted nowadays. Recently, multivariant MOFs have been demonstrated as versatile precursors to construct these mixed metal oxides. Herein, we synthesized four mixed Mn–Co oxide samples via simply annealing their MIL-53 precursors with different Co/Mn molar ratios. These four samples were dominated by three kinds of Mn–Co spinel phases. The mixed Mn–Co oxides showed enhanced ORR performances compared with the single metal counterparts in alkaline media. In particular, the sample containing a pure MnCo2O4 phase exhibited the highest activity with a half-wave potential of 0.772 V (vs. RHE), only 40 mV negative compared with that of commercial Pt/C. The H2O2 yield was calculated to be below 12.1%, corresponding to the high diffusion-limited current density along with the high electron transfer number. The surface defects, active Mn4+/Mn3+ and electrochemically active surface area together affected the ORR performances of these mixed Mn–Co oxides. The present work highlights the facile controllability of divalent MIL-53 analogues for highly efficient mixed Mn–Co oxides in ORR electrocatalysis. [ABSTRACT FROM AUTHOR]

We have found that the addition of proteins can greatly influence the light-induced self-assembly (LISA) behavior of bi-color thioglycolic acid (TGA)-capped CdTe Quantum Dots (QDs) and thus cause significant changes of their fluorescence (FL) signals (color and intensity), according to which a dual-channel FL sensor can be established for simultaneous discrimination of multiple proteins. The sensor is successfully used for the identification of ten native proteins and ten thermally denatured proteins and eight native proteins artificially added in human urine, respectively, during which process principal component analysis (PCA) is utilized to differentiate the targets based on their corresponding FL change patterns. This assay has provided a visual and simple method for the discrimination of various analytes, which may have great potential in the study of conformational changes of biomacromolecules and the analysis of real biological fluids. [ABSTRACT FROM AUTHOR]

Singly and doubly charged atomic ions of zinc and copper have been complexed with pyridine and held in an ion trap. Complexes involving Zn(ii) and Cu(i) (3d10) display a strong tendency to bind with H2O, whilst the Zn(i) (3d104s1) complexes exhibit a strong preference for the attachment of O2. DFT calculations show that this latter result can be interpreted as internal oxidation leading to the formation of superoxide complexes, [Zn(ii)O2−](pyridine)n, in the gas phase. The calculations also show that the oxidation of Zn(i) to form Zn(ii)O2−is promoted by a mixing of the occupied 4s and vacant 4p orbitals on the metal cation, and that this process is facilitated by the presence of the pyridine ligands. [ABSTRACT FROM AUTHOR]

Experiments on [Pb(H2O)n]2+complexes show that they require an unusually large number of water molecules (eleven) to stabilize the Pb2+ion against charge (proton) transfer. [ABSTRACT FROM AUTHOR]

A combined theoretical and experimental study of electronic transitions in the complex [Zn(pyridine)4]2+ provides the first example of a state-resolved electronic spectrum to be recorded for a dication complex in the gas phase. [ABSTRACT FROM AUTHOR]

The design of efficient mixed Mn-Co oxides as oxygen reduction reaction (ORR) electrocatalysts in alkaline media has been boosted nowadays. Recently, multivariant MOFs have been demonstrated as versatile precursors to construct these mixed metal oxides. Herein, we synthesized four mixed Mn-Co oxide samples via simply annealing their MIL-53 precursors with different Co/Mn molar ratios. These four samples were dominated by three kinds of Mn-Co spinel phases. The mixed Mn-Co oxides showed enhanced ORR performances compared with the single metal counterparts in alkaline media. In particular, the sample containing a pure MnCo 2 O 4 phase exhibited the highest activity with a half-wave potential of 0.772 V (vs. RHE), only 40 mV negative compared with that of commercial Pt/C. The H 2 O 2 yield was calculated to be below 12.1%, corresponding to the high diffusion-limited current density along with the high electron transfer number. The surface defects, active Mn 4+ /Mn 3+ and electrochemically active surface area together affected the ORR performances of these mixed Mn-Co oxides. The present work highlights the facile controllability of divalent MIL-53 analogues for highly efficient mixed Mn-Co oxides in ORR electrocatalysis.

Novel ruthenium complexes (MC113-MC117), obtained by modifying the terpyridine ligand of the black dye (N749), have been evaluated as sensitizers for dye sensitized solar cells (DSSCs). The modification is carried out by attaching selected chromophores, with varying electron donating strength, covalently to the central ring of the ligand. The complexes, compared to the parent dye, show red shifted absorption covering visible and near IR regions and higher molar extinction coefficients. We report in this work synthesis of a series of these ruthenium complexes with chromophores such as tert-butyl phenyl, triphenylamine, bithiophene, phenoxazine and phenothiazine. Detailed experimental characterization using optical, electrochemical and photovoltaic techniques has been carried out and complemented by density functional theory studies. The fill factors (ff) obtained for these dyes are larger than those of the parent black dye. In spite of these superior properties, the dyes show only moderate to good power conversion efficiencies. The possible reasons for this have been investigated and discussed.

Singly and doubly charged atomic ions of zinc and copper have been complexed with pyridine and held in an ion trap. Complexes involving Zn(II) and Cu(I) (3d(10)) display a strong tendency to bind with H(2)O, whilst the Zn(I) (3d(10)4s(1)) complexes exhibit a strong preference for the attachment of O(2). DFT calculations show that this latter result can be interpreted as internal oxidation leading to the formation of superoxide complexes, [Zn(II)O(2)(-)](pyridine)(n), in the gas phase. The calculations also show that the oxidation of Zn(I) to form Zn(II)O(2)(-) is promoted by a mixing of the occupied 4s and vacant 4p orbitals on the metal cation, and that this process is facilitated by the presence of the pyridine ligands.

Experiments on [Pb(H2O)n]2+ complexes show that they require an unusually large number of water molecules (eleven) to stabilize the Pb2+ ion against charge (proton) transfer.