Proteomics Defines Plasma Biomarkers for the Early Diagnosis of Biliary Atresia.

Early diagnosis of biliary atresia (BA) is crucial for improving the chances of survival and preserving the liver function of pediatric patients with BA. Herein, we performed proteomics analysis using data-independent acquisition (DIA) and parallel reaction monitoring (PRM) to explore potential biomarkers for the early diagnosis of BA compared to other non-BA jaundice cases. Consequently, we detected and validated differential protein expression in the plasma of patients with BA compared to the plasma of patients with intrahepatic cholestasis. Bioinformatics analysis revealed the enriched biological processes characteristic of BA by identifying the differential expression of specific proteins. Signaling pathway analysis revealed changes in the expression levels of proteins associated with an alteration in immunoglobulin levels, which is indicative of immune dysfunction in BA. The combination of polymeric immunoglobulin receptor expression and immunoglobulin lambda variable chain (IGL c2225_light_IGLV1-47_IGLJ2), as revealed via machine learning, provided a useful early diagnostic model for BA, with a sensitivity of 0.8, specificity of 1, accuracy of 0.89, and area under the curve value of 0.944. Thus, our study identified a possible effective plasma biomarker for the early diagnosis of BA and could help elucidate the underlying mechanisms of BA.

MAPK signaling pathway induced LOX-1+ polymorphonuclear myeloid-derived suppressor cells in biliary atresia.

Biliary atresia (BA) is a severe pediatric liver disease characterized by progressive bile duct destruction and fibrosis, leading to significant liver damage and frequently necessitating liver transplantation. This study elucidates the role of LOX-1+ polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in BA pathogenesis and assesses their potential as non-invasive early diagnostic biomarkers. Using flow cytometry, immunofluorescence, and molecular profiling, we analyzed the expression and activity of these cells in peripheral blood and liver tissues from BA patients and controls. Our findings reveal a significant increase in the frequencies and function of LOX-1+PMN-MDSCs in BA patients, along with MAPK signaling pathway upregulation, indicating their involvement in disease mechanisms. Additionally, the frequencies of LOX-1+PMN-MDSC in peripheral blood significantly positively correlate with liver function parameters in BA patients, demonstrating diagnostic performance comparable to traditional serum markers. These findings suggest that LOX-1+PMN-MDSCs contribute to the immunosuppressive environment in BA and could serve as potential diagnostic targets.

C─H Activation Enables the Construction of New Bis-Polyaryl Phenylpyridine Ruthenium Complexes: Conjugation and Rigidity Synergistic Effect for Advanced Electrochemiluminescence.

The access to bench-stable organometallic compounds unfolds new chemical space for medicinal and material sciences. In particular, stable organoruthenium compounds with constitutional and stereoisomeric forms for subtle regulation of electrochemiluminescence are intriguing and challenging. Here, coordination of polycyclic aromatic hydrocarbons on (2-phenylpyridine)2(CO)2Ru complex allows access to bis-polyaryl phenylpyridine (BPP) Ruthenium complex through C─H activation strategy and coupling reactions for installation of the functionalities with steric and electronic purposes. The photoluminescence and electrochemiluminescence of BPP Ru complexes are affected by the actual polycyclic aromatic hydrocarbons inherent properties. The anthracene derivatized BPP Ru complex (BPP-Ant) shows the best ECL performance and reveals an enormous ECL quantum efficiency of 1.6-fold higher than the golden standard Ru(bpy)3 2+. The unprecedentedly high efficiency is due to the best compromise between the structural conjugation and molecular rigidity from BPP-Ant providing a providential energy gap that facilitated the feasibility of electron transfer and favored the radiative energy release by experimentally and DFT calculations. Moreover, PL and spooling ECL spectroscopies are used to track and link multiple emission peaks of BPP-Ant at 445, 645, and 845 nm to different emissive species. These discoveries will add a new member to the efficient ECL ruthenium complex family and bring more potentials.

The association of immune-related genes and the potential role of IL10 with biliary atresia.

BACKGROUND: Biliary atresia (BA) is a severe immune-related disease that is characterized by biliary obstruction and cholestasis. The etiology of BA is unclear, our aim was to explore the relationship between biliary tract inflammation and immune-related genes. METHODS: We selected 14 SNPs in 13 immune-related genes and investigated their associations with BA by using a large case‒control cohort with a total of 503 cases and 1473 controls from southern China. RESULTS: SNP rs1518111 in interleukin10 (IL10) was identified as associated with BA (P = 5.79E-03; OR: 0.80; 95% CI: 0.68-0.94). The epistatic effects of the following pairwise interactions among these SNPs were associated with BA: signal transducer and activator of transcription 4 (STAT4) and chemokine (C-X-C motif) ligand 3 (CXCL3); STAT4 and damage-regulated autophagy modulator1 (DRAM1); CXCL3 and RAD51 paralog B (RAD51B); and interferon gamma (IFNG) and interleukin26 (IL26). Furthermore, we explored the potential role of IL-10 in the pathogenesis of the neonatal mouse model of BA. IL-10 effectively prevented biliary epithelial cell injury and biliary obstruction in murine BA as well as inhibit the activation of BA-related immune cells. CONCLUSIONS: In conclusion, this study provided strong evidence implicating IL10 as a susceptibility gene for BA in the southern Chinese population. IMPACT: This study provided strong evidence implicating IL10 as a susceptibility gene for BA in the southern Chinese population. This study could infer that IL-10 may play a protective role in BA mouse model. We found that four SNPs (rs7574865, rs352038, rs4622329, and rs4902562) have genetic interactions.

Self-enhanced peroxidase-like activity in a wide pH range enabled by heterostructured Au/MOF nanozymes for multiple ascorbic acid-related bioenzyme analyses.

Nanozymes, a class of catalytic nanomaterials, have shown great potential to substitute natural enzymes in various applications. Nevertheless, the pursuit of high-efficiency peroxidase-like activity in a wide pH range is one of the major challenges existing in designing nanozymes. A feasible strategy is to construct an artificial active center by using porous materials as stable supporting structures, which can actively modulate biocatalytic activities via their porous atomic structures and more active sites. Herein, a gold nanoparticles/metal-organic framework (MOF) heterostructure was prepared using UiO-66 as a stable support structure (Au NPs/UiO-66), which demonstrates enhanced peroxidase-like activity, ∼8.95 times higher than that of pure Au NPs. Strikingly, Au NPs/UiO-66 exhibits excellent stability (maintains above 80% activity at 40-70 °C and retains 93% activity after 3 months of storage) and sustained high relative activity (above 90%) over a pH range of 5.0-9.0 due to the homogeneous dispersibility of free-ligand Au NPs and the strong chemical interaction between the Au NPs and the UiO-66 host. Moreover, a colorimetric assay of ascorbic acid (AA) and three AA-related biological enzymes was developed based on Au NPs/UiO-66 nanozyme, which has a good linear detection range and excellent anti-interference ability. This work provides important guidance for the expansion of metal NPs/MOF heterostructure nanozymes and their application prospects in the development of biosensors.

Mechanistic explorations on the decarboxylative allylation of amino esters via dual photoredox and palladium catalysis.

Mechanistic studies reveal that the decarboxylative allylation of amino esters via dual photoredox and palladium catalysis occurs via oxidation giving π-allyl-Pd(II) species and carboxylate, which is oxidized by *Ir(III)-catalyst offering benzyl radicals. The alkylated product is formed via an SN2 pathway. Single-electron transfer between Pd(I)-species and Ir(II)-catalysis restores both catalysts.

Association between GPC2 polymorphisms and neuroblastoma risk in Chinese children.

BACKGROUND: The cell surface glycoprotein glypican 2 (GPC2) has been shown to increase susceptibility to neuroblastoma, which is the most common malignancy in children. However, associations between single nucleotide polymorphism(s) of GPC2 and neuroblastoma risk remain unclarified. METHODS: We conducted a case-control study to investigate two GPC2 polymorphisms (rs1918353 G>A and rs7799441 C>T) in 473 healthy controls and 402 pediatric patients with neuroblastoma. Single nucleotide polymorphism (SNP) genotyping was conducted on the samples by the TaqMan technique, and the data were subsequently analyzed by the t test, chi-squared test, and logistic regression model. In addition, we further performed stratification analysis by age, sex, tumor site of origin, or clinical stage to control confounding factors. RESULTS: According to the data of dominant models (GA/AA vs. GG: adjusted OR = 0.99, 95% CI = 0.76-1.29, p = 0.943; CT/TT vs. CC: adjusted OR = 0.91, 95% CI = 0.70-1.19, p = 0.498) or other comparisons, as well as the conjoint analysis (adjusted OR = 1.22, 95% CI = 0.93-1.59, p = 0.152), we unfortunately proved that the analysis of single or multiple loci did not support any significant association of GPC2 polymorphisms with susceptibility to neuroblastoma. CONCLUSION: GPC2 polymorphisms (rs1918353 G>A and rs7799441 C>T) are unable to statistically affect neuroblastoma risk in Chinese children. Therefore, more samples, especially from patients of various ethnic backgrounds, are required to increase the sample size and verify the effect of GPC2 polymorphisms on neuroblastoma risk in the presence of ethnic factor.

Dual-Site Activation Coupling with a Schottky Junction Boosts the Electrochemiluminescence of Carbon Nitride.

Robust electrochemiluminescence (ECL) of carbon nitride (CN) requires efficient electron-hole recombination and the suppression of electrode passivation. In this work, Au nanoparticles and single atoms (AuSA+NP ) loaded on CN serve as dual active sites that significantly accelerate charge transfer and activate peroxydisulfate. Meanwhile, the well-established Schottky junctions between Au NPs and CN act as electron sinks, effectively trapping over-injected electrons to prevent electrode passivation. As a result, the porous CN modified with AuSA+NP exhibits an enhanced and stable ECL emission, with a minimal relative standard deviation of 0.24 %. Furthermore, the designed ECL biosensor based on AuSA+NP -CN shows a remarkable performance in detecting organophosphorus pesticides. This innovative strategy has the potential to offer new insights into strong and stable ECL emission for practical applications.

CD177+ cells produce neutrophil extracellular traps that promote biliary atresia.

BACKGROUND & AIMS: We have previously reported on the potential pathogenic role of neutrophils in biliary atresia (BA). Herein, we aimed to delineate the role of CD177+ neutrophils in the pathogenesis of BA. METHODS: Immune cells from the livers of mice with rhesus rotavirus-induced BA were analysed. Single-cell RNA-sequencing was performed to specifically analyse Gr-1+ (Ly6C/Ly6G+) cells in the liver. Gene expression profiles of CD177+ cells were analysed using the Smart-Seq RNA-sequencing method, and the pathogenesis of BA was examined in Cd177-/- mice. Neutrophil extracellular trap (NET) inhibitors were used to determine the role of CD177+ cell-derived NETs in BA-associated bile duct damage, and a pilot clinical study evaluated the potential effects of N-acetylcysteine on NET release in BA. RESULTS: Increased levels of Gr-1+ cells were observed in the livers of mice with rhesus rotavirus-induced BA. RNA-sequencing analysis revealed that CD177+ cells were the main population of Gr-1+ cells and expressed elevated levels of both interferon-stimulated and neutrophil degranulation genes. Cd177-/- BALB/c mice exhibited delayed disease onset and reduced morbidity and mortality. High numbers of mitochondria were detected in CD177+ cells derived from mice with BA; these cells were associated with increased levels of reactive oxygen species and increased NET formation, which induced the apoptosis of biliary epithelial cells in cocultures. In a pilot clinical study, the administration of N-acetylcysteine to patients with BA reduced CD177+ cell numbers and reactive oxygen species levels, indicating a potential beneficial effect. CONCLUSIONS: Our data indicate that CD177+ cells play an important role in the initiation of BA pathogenesis via NET formation. CLINICAL TRIAL REGISTRATION: The pilot study of N-acetylcysteine treatment in patients with BA was registered on the Chinese Clinical Trial Registry (ChiCTR2000040505). LAY SUMMARY: Neutrophils (a type of innate immune cell, i.e. an immune cell that doesn't target a specific antigen) are thought to play a role in the development of biliary atresia (a rare but potentially lethal condition of the bile ducts that occurs in infants). Herein, we found that neutrophils expressing a particular protein (CD177) played an important role in bile duct damage by releasing a special structure (NET) that can trap and kill pathogens but that can also cause severe tissue damage. A pilot study in patients with biliary atresia showed that inhibiting NETs could have a beneficial effect.

Polymer Carbon Nanodots: A Novel Electrochemiluminophore for Dual Mode Detection of Ferric Ions.

The development of simple and effective dual-mode analytical methods plays crucial regulatory roles in the discrimination of relevant target species, because of their built-in cross reference correction and high accuracy. In this work, a novel polymer carbon nanodots (PCNDs) prepared from a facile one-pot hydrothermal procedure using readily available l-tryptophan and l-phenylalanine as precursors, showed excellent aqueous solubility and blue fluorescence property with a high quantum yield of 29%. Moreover, the PCNDs was demonstrated to be a robust luminophore with electrochemiluminescence (ECL) efficiency of 43% was achieved by using K2S2O8 as a coreactant. The spooling ECL spectroscopy was employed to take insight into excited states responsible for the potential-dependent ECL emissions. Most importantly, when introduced into construction of the fluorescence and ECL dual mode sensing platform, for the first time, the PCNDs displayed prominent performance for the detection of ferric ions (Fe3+). The ferric ions could be quantified ranging from micromolar to millimolar with a detection limit of 0.22 and 5.3 µM, respectively. Such a dual-functional sensing platform also exhibits excellent selectivity, reproducibility and stability. Results from this work indicate that PCNDs showing great promise as a bright luminophore for the fabrication of low-cost, high-performance dual-signal readout platforms for ferric ions determination.

Near-Infrared Electrogenerated Chemiluminescence from Simple Copper Nanoclusters for Sensitive Alpha-Fetoprotein Sensing.

Exploiting low cost, water-soluble, and near-infrared (NIR) emissive electrochemiluminophores (ECLphores) is significantly important for biological applications. In this study, bright and NIR electrogenerated chemiluminescence (ECL) emissive copper nanoclusters (Cu NCs) were synthesized through a facile one-pot wet chemical reduction method. ECL properties of obtained Cu NCs were examined in the presence of potassium persulfate, resulting in maximum intensity at 735 nm, at least 135 nm red-shifted with respect to all other Cu NCs. Electrochemistry, photoluminescence (PL), and spooling ECL spectroscopies were used to track NIR ECL emission of Cu NCs ascribed to the monomeric excited states. Due to the abundant binding sites of bovine serum albumin (BSA) to anchor target biomolecules, a sandwich-type ECL immunosensor was thus fabricated using such BSA-templated Cu NCs as tags and alpha fetoprotein antigen (AFP) as a model protein for the first time. Without assisting any signal amplification strategies, the proposed NIR ECL biosensor exhibited a wide linear range (1-400 ng mL-1) and low detection limit (0.02 ng mL-1) as well as superior selectivity and reproducibility and was successfully applied in real human serum sample determination. This work sets the stage for the development of novel non-noble metal nanoclusters for large-scale and emerging nanotechnology applications.

Down-regulation of STAT3 enhanced chemokine expression and neutrophil recruitment in biliary atresia.

Biliary atresia (BA) is an immune-related disorder and signal transducer and activator of transcription 3 (STAT3) is a key signalling molecule in inflammation. The present study was designed to clarify the function of STAT3 in BA. STAT3 expression was examined in patients and a mouse BA model in which STAT3 levels were further altered with a specific inhibitor or activator. Neutrophil accumulation and the levels of the neutrophil chemoattractants (C-X-C motif) ligand 1 (CXCL1) and IL-8 were determined. The effects of STAT3 inhibition on IL-8 expression were examined in human biliary epithelial cell (BEC) cultures. Functional changes in liver STAT3+ neutrophils in the mouse model were analysed with 10× single cell RNA-seq methods. Results showed STAT3 and p-STAT3 expression was reduced in BA liver tissue compared with control samples. Administration of a STAT3 inhibitor increased jaundice and mortality and reduced body weight in BA mice. In contrast, the STAT3 activator ameliorated BA symptoms. Extensive neutrophil accumulation together with CXCL1 up-regulation, both of which were suppressed by an anti-CXCL1 antibody, were observed in the STAT3 inhibitor-treated group. Recombinant IL-8 administration increased disease severity in BA mice, and the STAT3 activator had the reverse effect. Inhibiting STAT3 increased apoptosis of human BECs together with up-regulated IL-8 expression. RNA-seq analysis revealed reduced the numbers of STAT3 expressing neutrophil in BA which was accompanied by marked enhanced interferon-related antiviral activities. In conclusion, STAT3 reduction, enhanced IL-8 and CXCL1 expression and promoted the accumulation of interferon-responsive neutrophils resulting in BEC damage in BA.

Electrochemiluminescence of water-dispersed nitrogen and sulfur doped carbon dots synthesized from amino acids.

A facile one-pot hydrothermal approach for synthesizing water-dispersed nitrogen and sulfur doped carbon dots (NS-CDs) with high luminescence quantum yield was explored, using cysteine and tryptophan as precursors. The NS-CDs were characterized by means of FT-IR spectroscopy, XRD, TEM, etc. It was found that the absolute photoluminescence quantum yield (QY) of the NS-CDs determined with an integrating sphere can reach up to 73%, with an average decay time of 17.06 ns. Electrochemiluminescence (ECL) behaviors and mechanisms of the NS-CDs/K2S2O8 coreactant system were investigated. When the working electrode was modified with the prepared NS-CDs, the ECL efficiency of the NS-CDs with K2S2O8 was 24%, relative to Ru(bpy)3Cl2/K2S2O8. This work shows great potential for the NS-CDs to be used in bioanalytical applications.

De novo mutations in Caudal Type Homeo Box transcription Factor 2 (CDX2) in patients with persistent cloaca.

The cloaca is an embryonic cavity that is divided into the urogenital sinus and rectum upon differentiation of the cloacal epithelium triggered by tissue-specific transcription factors including CDX2. Defective differentiation leads to persistent cloaca in humans (PC), a phenotype recapitulated in Cdx2 mutant mice. PC is linked to hypo/hyper-vitaminosis A. Although no gene has ever been identified, there is a strong evidence for a genetic contribution to PC. We applied whole-exome sequencing and copy-number-variants analyses to 21 PC patients and their unaffected parents. The damaging p.Cys132* and p.Arg237His de novo CDX2 variants were identified in two patients. These variants altered the expression of CYP26A1, a direct CDX2 target encoding the major retinoic acid (RA)-degrading enzyme. Other RA genes, including the RA-receptor alpha, were also mutated. Genes governing the development of cloaca-derived structures were recurrently mutated and over-represented in the basement-membrane components set (q-value < 1.65 × 10-6). Joint analysis of the patients' profile highlighted the extracellular matrix-receptor interaction pathway (MsigDBID: M7098, FDR: q-value < 7.16 × 10-9). This is the first evidence that PC is genetic, with genes involved in the RA metabolism at the lead. Given the CDX2 de novo variants and the role of RA, our observations could potentiate preventive measures. For the first time, a gene recapitulating PC in mouse models is found mutated in humans.

Beta-amyloid deposition around hepatic bile ducts is a novel pathobiological and diagnostic feature of biliary atresia.

BACKGROUND AND AIMS: Biliary atresia (BA) is a poorly understood and devastating obstructive bile duct disease of newborns. It is often diagnosed late, is incurable and frequently requires liver transplantation. In this study, we aimed to investigate the underlying pathogenesis and molecular signatures associated with BA. METHODS: We combined organoid and transcriptomic analysis to gain new insights into BA pathobiology using patient samples and a mouse model of BA. RESULTS: Liver organoids derived from patients with BA and a rhesus rotavirus A-infected mouse model of BA, exhibited aberrant morphology and disturbed apical-basal organization. Transcriptomic analysis of BA organoids revealed a shift from cholangiocyte to hepatocyte transcriptional signatures and altered beta-amyloid-related gene expression. Beta-amyloid accumulation was observed around the bile ducts in BA livers and exposure to beta-amyloid induced the aberrant morphology in control organoids. CONCLUSION: The novel observation that beta-amyloid accumulates around bile ducts in the livers of patients with BA has important pathobiological implications, as well as diagnostic potential. LAY SUMMARY: Biliary atresia is a poorly understood and devastating obstructive bile duct disease of newborns. It is often diagnosed late, is incurable and frequently requires liver transplantation. Using human and mouse 'liver mini-organs in the dish', we unexpectedly identified beta-amyloid deposition - the main pathological feature of Alzheimer's disease and cerebral amyloid angiopathy - around bile ducts in livers from patients with biliary atresia. This finding reveals a novel pathogenic mechanism that could have important diagnostic and therapeutic implications.

Aggregation-Induced Electrochemiluminescence of Tetraphenylbenzosilole Derivatives in an Aqueous Phase System for Ultrasensitive Detection of Hexavalent Chromium.

Herein, aggregation-induced electrochemiluminescence (AIECL) of tetraphenylbenzosilole derivatives in an aqueous phase system with the participation of a co-reactant was systematically investigated for the first time. All organics that we studied exhibit excellent stability and dramatically enhanced electrochemiluminescence (ECL) and photoluminescence (PL) emission when the water fraction increases. The influence of substituents in the structure of tetraphenylbenzosilole derivatives on AIECL performance was proved by fluorescence, cyclic voltammetry, and related theoretical calculation. Among them, 2,3-bis(4-cyanophenyl)-1,1-diphenyl-benzosilole (TPBS-C) with strong electron-withdrawing cyano groups exhibits the best ECL behavior with the highest ECL efficiency (184.36%). The strongest ECL emission of TPBS-C not only stems from the aggregated molecules that restrict the intramolecular motion of peripheral phenyl groups, which inhibits the nonradiative transition, but also comes from the fact that TPBS-C has the lowest reduction potential, and twice the reduction process of TPBS-C occurs to produce more anion radicals (TPBS-C·-). Significantly, the ECL sensor based on TPBS-C nanoaggregates exhibits excellent detection performance for toxic Cr(VI) with a wide linear range from 10-12 to 10-4 M and an extremely low detection limit of 0.83 pM. This work developed an efficient luminophore with unique AIECL properties and realized the ultrasensitive detection of Cr(VI) in the aqueous phase system.

Depolymerization-Induced Electrochemiluminescence of Insoluble Porphyrin in Aqueous Phase.

Exploring efficient and robust electrochemiluminescence (ECL) performance of liposoluble porphyrins in aqueous phase for analytical purposes especially for important biological targets is still very challenging. In this work, a novel depolymerization-induced electrochemiluminescence (DIECL) of porphyrin and ß-cyclodextrin (ß-CD) self-assembly through a coreactant route was discovered. Among the studied meso-tetrasubstituted porphyrins, self-assembly of 5,10,15,20-tetrakis(4-hydroxyphenyl) porphyrin (THPP) and ß-CD (THPP@ß-CD) exhibits the best DIECL behavior with high efficiency (21.8%) as well as good reproducibility and stability. A mechanistic study suggests that the facile complexation of porphyrins with amphiphilic ß-CD via hydrogen bonding interaction greatly improves the water insolubility and the aggregation-caused deficient ECL of liposoluble porphyrins in aqueous solution. Furthermore, because of the strong hydrogen bonding between the hydroxyl groups on THPP@ß-CD and a highly electronegative substrate, such THPP@ß-CD is found to serve as an efficient luminophore for recognition of most electronegative fluoride (F-) in the aqueous phase with high sensitivity and selectivity, together with a low limit of detection (0.74 µΜ). The simplicity of this THPP@ß-CD and its unique DIECL property in current work provides a new guide for the ECL applications of liposoluble porphyrins in aqueous phase.

Encapsulation of Porphyrin-Fe/Cu Complexes into Coordination Space for Enhanced Selective Oxidative Dehydrogenation of Aromatic Hydrazides.

The encapsulation of specific nanoentities into hollow nanomaterials derived from metal organic frameworks has attracted continuous and growing research attentions owing to their unique structural properties and unusual synergistic functions. Herein, using the phase transformation of uniform rhombi dodecahedron ZIF-67, hollow nano-shell with a well-defined morphology is successfully prepared. Particularly, the iron-oxygen complex, that is formed by the interaction between TCPP-Fe/Cu (TCPP = tetrakis(4-carboxyphenyl)-porphyrin) and oxygen, can be acted as an ideal proton acceptor for practical organic reactions. Considering the unique adaptability of hollow ZIFs (named HZ) to the transformation of encapsulated TCPP-Fe/Cu bimetallic catalytic active sites, a heterogeneous catalyst (defined as HZ@TCPP-Fe/Cu) through morphology-controlled thermal transformation and rear assemble processes is designed and constructed. Under heterogeneous conditions, HZ@TCPP-Fe/Cu serves as a multifunctional molecular selector to promote the oxidative dehydrogenation of different aromatic hydrazide derivatives with high selectivity toward primary carbon among primary, secondary, and tertiary carbons that are unachievable by other traditional homogeneous catalysts. The high catalytic activity, selectivity, and recyclability of the catalyst proposed here are attractive advantages for an alternative route to the environmentally benign transformation of aromatic hydrazides to aromatic azobenzene.

Enhancing Charge Separation through Oxygen Vacancy-Mediated Reverse Regulation Strategy Using Porphyrins as Model Molecules.

Highly efficient charge separation has been demonstrated as one of the most significant steps playing decisive roles in enhancing the overall efficiency of photoelectrochemical (PEC) processes. In this study, by employing 5,10,15,20-tetrakis (4-carboxyphenyl) porphyrin-Ni (NiTCPP) as a prototype, an oxygen vacancy (Vo)-mediated reverse regulation strategy is proposed for tuning hole transfer, which in turn can accelerate the transport of electrons and thus enhancing charge separation. The optimal NiO/NiTCPP system exhibits much higher (≈40 times) photocurrent and longer (≈13 times) lifetime of charge carriers compared with those of pure NiTCPP. Furthermore, the electron transfer kinetic rate constant (Keff ) is quantitatively determined by an efficient scanning photoelectrochemical microscopy (SPECM). The Keff of the optimal system has a 5.7-fold improvement. In addition, the similar enhancement in charge separation from other semiconductors (CoTCPP and FeTCPP) are also observed, indicating that the Vo-mediated reverse regulation strategy is a promising pathway for tuning the properties of light harvesters in solar energy conversion.