A dual-signal output electrochemical aptasensor for glypican-3 ultrasensitive detection based on reduced graphene oxide-cuprous oxide nanozyme catalytic amplification strategy.

Glypican-3 (GPC3) is an essential reference target for hepatocellular carcinoma detection, follow-up and prediction. Herein, a dual-signal electrochemical aptasensor based on reduced graphene oxide-cuprous oxide (RGO-Cu2O) nanozyme was developed for GPC3 detection. The RGO-Cu2O nanoenzyme displayed excellent electron transport effect, large specific surface area and outstanding peroxidase-like ability. The differential pulse voltammetry (DPV) signal of Cu2O oxidation fraction and the chronoamperometry (i-t) signal of H2O2 decomposition catalyzed by RGO-Cu2O nanozyme were used as dual-signal detection. Under optimal conditions, the log-linear response ranges were 0.1 to 500.0 ng/mL with the limit of detection 0.064 ng/mL for DPV technique, and 0.1-50.0 ng/mL for i-t technique (detection limit of 0.0177 ng/mL). The electrochemical aptasensor has remarkably analytical performance with wide response range, low detection limit, excellent repeatability and specificity, good recovery in human serum samples. The two output signals of one sample achieve self-calibration of the results, effectively avoiding the occurrence of possible leakage and misdiagnosis of a single detection signal, suggesting that it will be a promising method in the early biomarker detection.

AURKA emerges as a vulnerable target for KEAP1-deficient non-small cell lung cancer by activation of asparagine synthesis.

AURKA is an established target for cancer therapy; however, the efficacy of its inhibitors in clinical trials is hindered by differential response rates across different tumor subtypes. In this study, we demonstrate AURKA regulates amino acid synthesis, rendering it a vulnerable target in KEAP1-deficient non-small cell lung cancer (NSCLC). Through CRISPR metabolic screens, we identified that KEAP1-knockdown cells showed the highest sensitivity to the AURKA inhibitor MLN8237. Subsequent investigations confirmed that KEAP1 deficiency heightens the susceptibility of NSCLC cells to AURKA inhibition both in vitro and in vivo, with the response depending on NRF2 activation. Mechanistically, AURKA interacts with the eIF2α kinase GCN2 and maintains its phosphorylation to regulate eIF2α-ATF4-mediated amino acid biosynthesis. AURKA inhibition restrains the expression of asparagine synthetase (ASNS), making KEAP1-deficient NSCLC cells vulnerable to AURKA inhibitors, in which ASNS is highly expressed. Our study unveils the pivotal role of AURKA in amino acid metabolism and identifies a specific metabolic indication for AURKA inhibitors. These findings also provide a novel clinical therapeutic target for KEAP1-mutant/deficient NSCLC, which is characterized by resistance to radiotherapy, chemotherapy, and targeted therapy.

Strain Regulation of Mixed-Halide Perovskites Enables High-Performance Wide-Bandgap Photovoltaics.

Wide-bandgap mixed-halogen perovskite materials are widely used as top cells in tandem solar cells. However, serious open-circuit voltage (Voc ) loss restricts the power conversion efficiency (PCE) of wide-bandgap perovskite solar cells (PSCs). Herein, it is shown that the resulting methylammonium vacancies induce lattice distortion in methylammonium chloride-assisted perovskite film, resulting in an inhomogeneous halogen distribution and low Voc . Thus, a lattice strain regulation strategy is reported to fabricate high-performance wide-bandgap PSCs. Rubidium (Rb) cations are introduced to fill the A-site vacancy caused by the methylammonium volatilization, which alleviates shrinkage strain of the perovskite crystal. The reduced lattice distortion and increased halide ion migration barrier result in a homogeneous mixed-halide perovskite film. Due to improved carrier transport and suppressed nonradiative recombination, the Rb-treated wide-bandgap PSC (1.68 eV) achieves an excellent PCE of 21.72%, accompanied by a high Voc of 1.22 V. The resulting device maintains more than 90% of its initial PCE after 1500 h under 1-sun illumination conditions.

Design, synthesis and evaluation of C-5 substituted pyrrolopyridine derivatives as potent Janus Kinase 1 inhibitors with excellent selectivity.

The development of highly selective Janus Kinase 1 (JAK1) inhibitors is crucial for improving efficacy and minimizing adverse effects in the clinical treatment of autoimmune diseases. In a prior study, we designed a series of C-5 4-pyrazol substituted pyrrolopyridine derivatives that demonstrated significant potency against JAK1, with a 10 âˆ¼ 20-fold selectivity over Janus Kinase 2 (JAK2). Building on this foundation, we adopted orthogonal strategy by modifying the C-5 position with 3-pyrazol/4-pyrazol/3-pyrrol groups and tail with substituted benzyl groups on the pyrrolopyridine head to enhance both potency and selectivity. In this endeavor, we have identified several compounds that exhibit excellent potency and selectivity for JAK1. Notably, compounds 12b and 12e, which combined 4-pyrazol group at C-5 site and meta-substituted benzyl tails, displayed IC50 value with 2.4/2.2 nM and high 352-/253-fold selectivity for JAK1 over JAK2 in enzyme assays. Additionally, both compounds showed good JAK1-selective in Ba/F3-TEL-JAK1/2 cell-based assays. These findings mark a substantial improvement, as these compounds are 10-fold more potent and over 10-fold more selective than the best compound identified in our previous study. The noteworthy potency and selectivity properties of compounds 12b and 12e suggest their potential utility in furthering the development of drugs for autoimmune diseases.

A stepwise strategy integrating dynamic stress CT myocardial perfusion and deep learning-based FFRCT in the work-up of stable coronary artery disease.

OBJECTIVES: To validate a novel stepwise strategy in which computed tomography-derived fractional flow reserve (FFRCT) is restricted to intermediate stenosis on coronary computed tomography angiography (CCTA) and computed tomography myocardial perfusion imaging (CT-MPI) was reserved for vessels with gray zone FFRCT values. MATERIALS AND METHODS: This retrospective study included 87 consecutive patients (age, 58 ± 10 years; 70% male) who underwent CCTA, dynamic CT-MPI, interventional coronary angiography (ICA), and fractional flow reserve (FFR) for suspected or known coronary artery disease. FFRCT was computed using a deep learning-based platform. Three stepwise strategies (CCTA + FFRCT + CT-MPI, CCTA + FFRCT, CCTA + CT-MPI) were constructed and their diagnostic performance was evaluated using ICA/FFR as the reference standard. The proportions of vessels requiring further ICA/FFR measurement based on different strategies were noted. Furthermore, the net reclassification index (NRI) was calculated to ascertain the superior model. RESULTS: The CCTA + FFRCT + CT-MPI strategy yielded the lowest proportion of vessels requiring additional ICA/FFR measurement when compared to the CCTA + FFRCT and CCTA + CT-MPI strategies (12%, 22%, and 24%). The CCTA + FFRCT + CT-MPI strategy exhibited the highest accuracy for ruling-out (91%, 84%, and 85%) and ruling-in (90%, 85%, and 85%) functionally significant lesions. All strategies exhibited comparable sensitivity for ruling-out functionally significant lesions and specificity for ruling-in functionally significant lesions (p > 0.05). The NRI indicated that the CCTA + FFRCT + CT-MPI strategy outperformed the CCTA + FFRCT strategy (NRI = 0.238, p < 0.001) and the CCTA + CT-MPI strategy (NRI = 0.233%, p < 0.001). CONCLUSIONS: The CCTA + FFRCT + CT-MPI stepwise strategy was superior to the CCTA + FFRCT strategy and CCTA+ CT-MPI strategy by minimizing unnecessary invasive diagnostic catheterization without compromising the agreement rate with ICA/FFR. CLINICAL RELEVANCE STATEMENT: Our novel stepwise strategy facilitates greater confidence and accuracy when clinicians need to decide on interventional coronary angiography referral or deferral, reducing the burden of invasive investigations on patients. KEY POINTS: • A stepwise CCTA + FFRCT + CT-MPI strategy holds promise as a viable method to reduce the need for invasive diagnostic catheterization, while maintaining a high level of agreement with ICA/FFR. • The CCTA + FFRCT + CT-MPI strategy performed better than the CCTA + FFRCT and CCTA + CT-MPI strategies. • A stepwise CCTA + FFRCT + CT-MPI strategy allows to minimize unnecessary invasive diagnostic catheterization and helps clinicians to referral or deferral for ICA/FFR with more confidence.

Effects of microplastics on N2O production and reduction potential in crop soils of northern China.

Microplastics (MPs) pollution are found to be increasing in vegetable soils and potentially affecting N2O production and their associated pathways; however, its specific effects remain unclear. Here, we selected two common MPs, PE and PP at four different concentration levels of 0, 0.5, 1.5 and 3%, and conducted several incubation experiments aiming to explore soil bacterial and fungal N2O production. Results showed that the bacteria were the main contributors for the production of N2O, regardless of the absence or presence of MPs; and its contribution was decreased with increasing concentrations of PE and PP. The nosZ clade I and II genes were positively correlated with N2O reduction rates, indicating a combined regulation on soil N2O reduction. PE significantly inhibited the bacterial nitrification and denitrification, but did not affect the total N2O production rates; while PP significantly reduced both the bacterial and fungal N2O production rates. The resistance of fungal N2O production to MPs pollution was stronger than that of the bacterial N2O production. It highlights that the MPs pollution could reduce the potential of N2O production and reduction, and thus disturb soil nitrogen cycling system; while the inhibition on N2O production via bacteria and fungi varies with different types of MPs. This study is conducive to an improved and more comprehensive understanding of the ecological impacts of MPs within the agroecosystem.

Serum IGFBP-1 as a promising diagnostic and prognostic biomarker for colorectal cancer.

Our previous study showed that levels of circulating insulin-like growth factor binding protein-1 (IGFBP-1) has potential diagnostic value for early-stage upper gastrointestinal cancers. This study aimed to assess whether serum IGFBP-1 is a potential diagnostic and prognostic biomarker for CRC patients. IGFBP-1 mRNA expression profile data of peripheral blood in colorectal cancer (CRC) patients were downloaded and analyzed from Gene Expression Omnibus database. We detected serum IGFBP-1 in 138 CRC patients and 190 normal controls using enzyme-linked immunosorbent assay. Blood IGFBP-1 mRNA levels were higher in CRC patients than those in normal controls (P = 0.027). In addition, serum IGFBP-1 protein levels in the CRC group were significantly higher than those in normal control group (P < 0.0001). Serum IGFBP-1 demonstrated better diagnostic accuracy for all CRC and early-stage CRC, respectively, when compared with carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA 19-9) or the combination of CEA and CA19-9. Furthermore, Cox multivariate analysis revealed that serum IGFBP-1 was an independent prognostic factor for OS (HR = 2.043, P = 0.045). Our study demonstrated that serum IGFBP-1 might be a potential biomarker for the diagnosis and prognosis of CRC. In addition, the nomogram might be helpful to predict the prognosis of CRC.

A cascade signal-amplified fluorescent biosensor combining APE1 enzyme cleavage-assisted target cycling with rolling circle amplification.

A cascade signal-amplified fluorescent biosensor was developed for miRNA-21 detection by combining APE1 enzyme-assisted target recycling and rolling circle amplification strategy. A key feature of this biosensor is its dual-trigger mechanism, utilizing both tumor-endogenous miRNA-21 and the APE1 enzyme in the initial amplification step, followed by a second rolling circle amplification reaction. This dual signal amplification cascade significantly enhanced sensitivity, achieving a detection limit of 3.33 pM. Furthermore, this biosensor exhibited excellent specificity and resistance to interference, allowing it to effectively distinguish and detect the target miRNA-21 in the presence of multiple interfering miRNAs. Moreover, the biosensor maintained its robust detection capabilities in a 10% serum environment, demonstrating its potential for clinical disease diagnosis applications.

The Presence, Location, and Degree of Late Gadolinium Enhancement in Relation to Myocardial Dysfunction and Poor Prognosis in Patients with Systemic Lupus Erythematosus.

Patients with systemic lupus erythematosus (SLE) typically develop myocardial fibrosis. No studies have investigated the clinical significance of the presence, location, and degree of fibrosis in SLE patients. Seventy-four SLE patients were included. Thirty-seven non-autoimmune disease patients and thirty-seven healthy individuals were included as controls. Myocardial fibrosis was evaluated at cardiac magnetic resonance via a qualitative and quantitative assessment of late gadolinium enhancement (LGE). Myocardial function was measured via speckle-tracking echocardiography. All patients were followed up for the occurrence of major adverse cardiac events (MACE). The presence, locations, and degrees of LGE disturbed regional and global myocardial function. The presence of LGE, left ventricular free-wall LGE (LVFW LGE), and severe LGE were all independent predictors of MACE in SLE patients [LGE presence HR: 3.746 (1.434-9.79), p = 0.007; LVFW LGE HR: 2.395 (1.023-5.606), p = 0.044; severe LGE HR: 3.739 (1.241-11.266), p = 0.019]. LGE combined with SLE-related organ damage identified patients at high risk of MACE (p < 0.001). In conclusion, the presence, degree, and location of LGE were associated with myocardial dysfunction. The presence, location, and degree of LGE had the potential to independently predict poor prognosis and improve risk stratification in SLE patients.

Reduced graphene oxide-persimmon tannin/Pt@Pd nanozyme-based cascade colorimetric sensor for detection of 1,5-anhydroglucitol.

1,5-anhydroglucitol (1,5-AG) is of considerable clinical relevance as a biochemical marker of glucose metabolism in the assessment and monitoring of diabetes. Herein, a simple colorimetric biosensor was constructed for the identification and detection of 1,5-AG by using pyranose oxidase (PROD) enzyme cascaded with reduced graphene oxide/persimmon tannin/Pt@Pd (RGO-PT/Pt@Pd NPs) nanozyme. The as-prepared RGO-PT/Pt@Pd NPs had excellent peroxidase-like activity and can be applied as a nanozyme. First, PROD enzyme reacts with the target 1,5-AG, decomposing 1,5-AG into 1,5-anhydrofuctose (1,5-AF) and H2O2. At this point, the highly catalytic RGO-PT/Pt@Pd NPs nanozyme produces a cascade with PROD enzyme which catalyzes the decomposition of H2O2 to produce O2. This in turn oxidizes the substrate 3,3',5,5'-tetramethylbenzidine (TMB) and produces a color change in the solution. Finally, the detection of 1,5-AG was achieved by measuring the absorption peak at 652 nm with an ultraviolet visible (UV-vis) spectrophotometer. Under optimal conditions, the linear operating range of the 1,5-AG enzyme cascade colorimetric sensor was 1.0-100.0 µg/mL, and the limit of detection (LOD) was 0.81 µg/mL. The proposed colorimetric biosensor was successfully applied to detect 1,5-AG in spiked human serum samples with the recoveries of 97.2-103.9% and RSDs of 1.94-4.48%. It provides a promising developmental assay for clinical detection of 1,5-AG.

Salvianolic acid B attenuates inflammation and prevent pathologic fibrosis by inhibiting CD36-mediated activation of the PI3K-Akt signaling pathway in frozen shoulder.

Frozen shoulder (FS) is characterized by pain and limited range of motion (ROM). Inflammation and fibrosis are accepted as main pathologic processes associated with the development of FS. However, the intrinsic mechanisms underlying pathologic fibrosis remain unclear. We aimed to elucidate the key molecules involved in pathologic fibrosis and explore new therapeutic targets for FS. Synovial fibroblasts isolated from patient biopsies were identified using immunofluorescence. Western blotting, RT-qPCR, cell adhesion tests, and would-healing assays were used to evaluate the fibrosis-related functions of synovial fibroblasts. Elevated cluster of differentiation 36 (CD36) expression was detected in FS using Western blotting and immunohistochemistry. Salvianolic acid b (SaB) inhibited CD36, blocking synovial fibroblast-induced inflammation and fibrosis. Our RNA-seq data showed that knocking down CD36 dramatically impaired the capacity of synovial fibroblasts for cell adhesion and that the PI3K-Akt signaling pathway may be crucial to the fibrotic process of FS. By up-regulating CD36 and inhibiting the phosphorylation of Akt, we demonstrated that CD36 promotes pathologic fibrosis by activating the PI3k-Akt pathway. Finally, rats treated with SaB had improved ROM and less collagen fiber deposition than the FS model group. Conclusion: SaB attenuates inflammation and inhibited the CD36-mediated activation of the PI3K-Akt signaling pathway to block pathologic fibrosis of FS in vitro and in vivo models.

Association between resting myocardial work indices and stress myocardial perfusion in patients with angina and non-obstructive coronary artery disease.

Background: Myocardial work (MW) indices and longitudinal strain (LS) are sensitive markers of early left ventricular systolic dysfunction. Stress computed tomography myocardial perfusion imaging (CT-MPI) can assess early myocardial ischemia. The association between resting MW indices and stress myocardial perfusion remains unclear. This study compares resting MW indices with LS to assess stress myocardial perfusion in angina patients with non-obstructive coronary artery disease (CAD). Methods: Eighty-four patients who underwent resting echocardiography, coronary computed tomography angiography, and stress CT-MPI were reviewed. Seventeen myocardial segments were divided into three regions according to the epicardial coronary arteries. Global indices included global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE). Regional indices included regional longitudinal strain (RLS), regional work index (RWI), and regional work efficiency (RWE). Reduced global perfusion was defined as an average stress myocardial blood flow (MBF) <116 mL/100 mL/min for the whole heart. Reduced regional perfusion was defined as an average stress MBF <116 mL/100 mL/min for the coronary territories. No patients demonstrated obstructions in the epicardial coronary arteries (stenosis diameter <50%). The MW indices and LS were compared. Receiver operating characteristic curves were constructed and logistic regression analyses were used to investigate the predictors of reduced myocardial perfusion. Results: Patients with reduced stress perfusion demonstrated reduced GLS, GWI, GCW, and GWE (P<0.05) and increased GWW (P<0.05). After adjustment for age and sex, GWE was still independently associated with reduced myocardial perfusion (odds ratio =0.386, 95% confidence interval: 0.214-0.697; P<0.05). Receiver operating characteristic curves reflected the good diagnostic ability of GWE and its superiority to GLS (area under the curve: 0.858 vs. 0.741). The optimal cutoff GWE value was 95% (sensitivity, 70%; specificity, 90%). Regions with lower stress perfusion showed lower RLS, RWI, and RWE (P<0.05). The optimal cutoff value of RWE for predicting reduced regional perfusion was 95%, with an area under the curve of 0.780, a sensitivity of 62%, and a specificity of 83%. Conclusions: Resting MW indices perform well in assessing global and regional stress myocardial perfusion in angina patients with non-obstructive CAD, and GWE is superior to GLS in the global evaluations.

The diagnostic value of serum insulin-like growth factor binding protein 7 in gastric cancer.

Backgrounds: Early detection might help in reducing the burden and promoting the survival rate of gastric cancers. Herein, we tried to explore the diagnostic value of insulin-like growth factor binding protein 7 (IGFBP7) in gastric cancers. Methods: In this study, we first analyzed the expression levels and prognostic value of IGFBP7 mRNA in gastric cancers from The Cancer Genome Atlas (TCGA) database. Then, we recruited 169 gastric cancer patients and 100 normal controls as training cohort, and 55 gastric cancer patients and 55 normal controls as independent validation cohort. Enzyme-linked immunosorbent assay was applied to test the serum levels of IGFBP7. The receiver operating characteristic curve (ROC) and the area under the curve (AUC) were applied to evaluation the diagnostic value. Results: TCGA showed that IGFBP7 mRNA was dysregulated and associated with prognosis in gastric cancer patients. Then, we examined the expression of serum IGFBP7 and found that serum IGFBP7 expressed lower in gastric cancer patients than normal controls both in training and independent validation cohorts (p < 0.0001). In training cohort, with the cutoff value of 1.515 ng/ml, the AUC for distinguishing gastric cancer patients was 0.774 (95% CI [0.713-0.836]) with sensitivity of 36.7% (95% CI [29.5-44.5]) and specificity of 90.0% (95% CI [82.0-94.8]). As for early-stage EJA, the AUC was 0.773 (95% CI [0.701-0.845]) with the sensitivity of 33.3% (95% CI [14.4-58.8]). In independent validation cohort, with the same cutoff value, the AUC reached to 0.758 (95% CI [0.664-0.852]). Similarly, for early-stage gastric cancer diagnosis in the independent validation cohort, the AUC value was 0.778 (95% CI [0.673-0.882]). Conclusions: This study indicated that serum IGFBP7 might act as a potential early diagnostic marker for gastric cancers.

Lattice Strain Regulation Enables High-Performance Formamidinium Perovskite Photovoltaics.

Formamidinium lead iodide (FAPbI3 ) perovskite possesses an ideal optical bandgap and is a potential material for fabricating the most efficient single-junction perovskite solar cells (PSCs). Nevertheless, large formamidinium (FA) cations result in residual lattice strain, which reduces the power conversion efficiency (PCE) and operational stability of PSCs. Herein, the modulation of lattice strain in FAPbI3 crystals via a π-conjugated organic amine, i.e., 4-pyrene oxy butylamine (PYBA), is proposed. PYBA pairs at the grain boundary serve as a template for the crystallization of FAPbI3 perovskite, thereby inducing a highly oriented crystal and a pure α-phase film. The PYBA pairs with strong π-π interactions provide a solid fulcrum for external compression strain, thus compensating for the inherent tension strain of FAPbI3 crystals. The strain release elevates the valence band of the perovskite crystals, thereby decreasing the bandgap and trap density. Consequently, the PYBA-regulated FAPbI3 PSC achieves an excellent PCE of 24.76%. Moreover, the resulting device exhibits improves operational stability and maintains over 80% of its initial PCE after 1500 h under maximum power point tracking conditions.

H-rGO-Pd NPs Nanozyme Enhanced Silver Deposition Strategy for Electrochemical Detection of Glypican-3.

Glypican-3 (GPC3), as an emerging biomarker, has been shown to be beneficial for the early diagnosis and treatment of hepatocellular carcinoma (HCC). In this study, an ultrasensitive electrochemical biosensor for GPC3 detection has been constructed based on the hemin-reduced graphene oxide-palladium nanoparticles (H-rGO-Pd NPs) nanozyme-enhanced silver deposition signal amplification strategy. When GPC3 specifically interacted with GPC3 antibody (GPC3Ab) and GPC3 aptamer (GPC3Apt), an "H-rGO-Pd NPs-GPC3Apt/GPC3/GPC3Ab" sandwich complex was formed with peroxidase-like properties which enhanced H2O2 to reduce the silver (Ag) ions in solution to metallic Ag, resulting in the deposition of silver nanoparticles (Ag NPs) on the surface of the biosensor. The amount of deposited Ag, which was derived from the amount of GPC3, was quantified by the differential pulse voltammetry (DPV) method. Under ideal circumstances, the response value was linearly correlated with GPC3 concentration at 10.0-100.0 µg/mL with R2 of 0.9715. When the GPC3 concentration was in the range from 0.01 to 10.0 µg/mL, the response value was logarithmically linear with the GPC3 concentration with R2 of 0.9941. The limit of detection was 3.30 ng/mL at a signal-to-noise ratio of three and the sensitivity was 1.535 µAµM-1cm-2. Furthermore, the electrochemical biosensor detected the GPC3 level in actual serum samples with good recoveries (103.78-106.52%) and satisfactory relative standard deviations (RSDs) (1.89-8.81%), which confirmed the applicability of the sensor in practical applications. This study provides a new analytical method for measuring the level of GPC3 in the early diagnosis of HCC.

PtSnBi Nanoplates Enable Photoacoustic Imaging-Guided Highly Efficient Photothermal Tumor Ablation.

The development of photothermal agents (PTAs) with robust photostability and high photothermal conversion efficiency is of great importance for cancer photothermal therapy. Herein, a novel PTA was created using two-dimensional intermetallic PtSnBi nanoplates (NPs), which demonstrated excellent photostability and biocompatibility with a high photothermal conversion efficiency of ∼61 % after PEGylation. More importantly, PtSnBi NPs could be employed as photoacoustic imaging contrast agents for tumor visualization due to their strong absorbance in the NIR range. In addition, both in vitro and in vivo experiments confirmed that PtSnBi NPs had a good photothermal efficacy under NIR laser irradiation. Therefore, the remarkable therapeutic characteristics of PtSnBi NPs make them a most promising candidate for cancer theranostics.

Design of the Synergistic Rectifying Interfaces in Mott-Schottky Catalysts.

The functions of interfacial synergy in heterojunction catalysts are diverse and powerful, providing a route to solve many difficulties in energy conversion and organic synthesis. Among heterojunction-based catalysts, the Mott-Schottky catalysts composed of a metal-semiconductor heterojunction with predictable and designable interfacial synergy are rising stars of next-generation catalysts. We review the concept of Mott-Schottky catalysts and discuss their applications in various realms of catalysis. In particular, the design of a Mott-Schottky catalyst provides a feasible strategy to boost energy conversion and chemical synthesis processes, even allowing realization of novel catalytic functions such as enhanced redox activity, Lewis acid-base pairs, and electron donor-acceptor couples for dealing with the current problems in catalysis for energy conversion and storage. This review focuses on the synthesis, assembly, and characterization of Schottky heterojunctions for photocatalysis, electrocatalysis, and organic synthesis. The proposed design principles, including the importance of constructing stable and clean interfaces, tuning work function differences, and preparing exposable interfacial structures for designing electronic interfaces, will provide a reference for the development of all heterojunction-type catalysts, electrodes, energy conversion/storage devices, and even super absorbers, which are currently topics of interest in fields such as electrocatalysis, fuel cells, CO2 reduction, and wastewater treatment.

Microscopic mechanism study of the rheological behavior of non-Newtonian fluids based on dissipative particle dynamics.

Non-Newtonian fluid rheological properties are a hot research topic for realizing intelligent applications. In order to investigate the microscopic mechanism and structural evolution process of the nonlinear rheological behavior of non-Newtonian fluids, this paper systematically investigates two continuous nonlinear rheological behaviors of non-Newtonian fluids, namely shear-thickening and shear-thinning rheological properties, using a non-Newtonian fluid system composed of polyethylene glycol (PEG) mixed with nano-silica (Nano-SiO2) by a dissipative particle dynamics (DPD) method. It is shown that at low shear rates, the molecular chains of PEG in the fluid are stretched due to shear flow and the molecular structure is transformed into an ordered state; and the effective hydrodynamic radius of Nano-SiO2 beads decreases, which makes the translational friction coefficient of the beads decrease and the system mobility increases, exhibiting shear-thinning behavior. When the shear rate exceeds the critical value, the contact and collision probability between Nano-SiO2 beads in the non-Newtonian fluid increases; a large number of silicon hydroxyl groups exist on the surface of Nano-SiO2, which form a large number of hydrogen bonds when they are close to each other and constrain the particle separation, resulting in a large aggregation of Nano-SiO2 beads, leading to an increase in the effective kinetic radius of Nano-SiO2 beads and an increase in the coefficient of translational friction, forming a blockage of the fluid system and exhibiting a shear-thickening behavior. Our study provides insights for understanding the rheological behavior of non-Newtonian fluids from a microscopic perspective, and contributes to the intelligent application of non-Newtonian fluids.

A label-free electrochemical aptasensor based on platinum@palladium nanoparticles decorated with hemin-reduced graphene oxide as a signal amplifier for glypican-3 determination.

Glypican-3 (GPC3) is a membrane-associated proteoglycan that is specifically upregulated in hepatocellular carcinoma (HCC) and has become one of the most promising biomarkers closely related to the occurrence and development of HCC. In this work, platinum@palladium nanoparticles decorated with hemin-reduced graphene oxide (H-rGO-Pt@Pd NPs) were used not only as a support for GPC3 aptamer (GPC3Apt) immobilization, but also as a new redox nanoprobe in electrochemical analysis for the determination of GPC3. The electrochemical aptasensor involved a reaction cell with a three-electrode system, and the differential pulse voltammetry (DPV) technique was adopted. In the presence of GPC3, the formed GPC3Apt-GPC3 complexes had stable structures and were cleaved from the electrode surface, leading to more electroactive H-rGO-Pt@Pd NPs repelling freely from the GPC3Apt/H-rGO-Pt@Pd NPs and thus to the increase of the oxidation peak current of hemin in H-rGO-Pt@Pd NPs. Under optimal conditions and a working voltage of +700 mV (vs. Ag/AgCl), the label-free electrochemical GPC3 aptasensor showed superior performance with a wider concentration linear range (0.001-10.0 µg mL-1), a lower limit of detection (LOD) (0.181 ng mL-1, S/N = 3), a higher sensitivity (0.0446 µA µM-1 cm-2) and good selectivity. Furthermore, the fabricated aptasensor was applied to GPC3 determination in human serum samples with satisfactory recoveries of 94.3%-119% and RSDs of 0.15%-5.78%. The current work provides a flexible approach for the rapid and sensitive analysis of GPC3 and has a broad application prospect in the diagnosis of HCC.