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As a “star material”, 2D transition metal carbides and/or nitrides (MXenes) have tremendous potential applications in biosensor development and molecular imaging. MXenes have a lot of advantages due to their large specific surface, excellent electrical conductivity, adjustable band gap, and easy modification. MXenes that immobilized with DNA strands, proteins, enzymes, or other bioluminescent materials on the surface, have been used to measure small molecules with extraordinary sensitivity and remarkable limit of detection. This review provides an overview of most recent development in the synthesis, fundamental properties, biosensing, and molecular imaging applications of MXenes. We focused on molecular detection through MXene-based electrochemical properties their challenges and novel opportunities of MXenes in biological applications. This article will provide a guide for researchers who are interested in the application of MXenes biosensors.

Metal–organic framework (MOF)-derived catalysts are widely used for CO2 electroreduction to formate. However, the effect of the local coordination environment of MOF precursors on CO2 electroreduction activity is still unclear. Herein, Pb-MOF precursors with different coordination environments were synthesized by electrodeposition (Pb-MOF-e) and hydrothermal (Pb-MOF-t) methods, respectively. The coordination environment in Pb-MOF-t has eight O sites of benzene-1,3,5-tricarboxylate (BTC) ligands and one O site from H2O, while Pb-MOF-e has seven O sites of BTC ligands and two O sites from H2O. Pb-MOF-e and Pb-MOF-t could be derived into 4 and 70 nm particles on Pb and carbon paper (CP), and the catalysts are named Pb NP-e/Pb, Pb NP-e/CP, and Pb NP-t/CP. In particular, Pb NP-e/Pb exhibited higher formate selectivity (92.0%), with a maximum formate formation rate of 2734.5 μmol cm–1 h–1 at −2.4 V (vs Ag/Ag+), which is 4.7 and 5.8 times higher than that Pb NP-e/CP and Pb NP-t/CP. The experimental results showed that Pb-MOF-e has evolved structurally to form Pb nanoparticles with large an electrochemically active surface area, low interfacial transport resistance, and low adsorption potential of CO2·– intermediates. In addition, the edge of Pb nanoparticles as the active site could efficiently stabilize the *OCHO intermediate and enhance the activity. The obtained Pb NP-e/Pb catalyst shows promising prospects in CO2 electroreduction applications. [ABSTRACT FROM AUTHOR]

Wellbore instability caused by hydration during the development of shale gas reservoirs poses significant challenges to drilling engineering. In this study, a novel and environmentally friendly shale inhibitor, TIL-NH2, was synthesized via free radical polymerization using 1-vinylimidazole and N-(2-bromoethyl)-1,3-propanediamine dihydrobromide as the main raw materials. The molecular structure of TIL-NH2 was characterized by infrared spectroscopy and nuclear magnetic resonance. Incorporating imidazole cations and amino bifunctional groups, TIL-NH2 exhibits excellent inhibitory performance and environmental friendliness. Its performance was systematically evaluated through linear swelling tests, shale cuttings rolling recovery tests, permeability recovery experiments, and dynamic adsorption analyses. The results indicate the following: (1) At a concentration of 1.2 wt%, TIL-NH2 reduced the linear swelling height of shale by 65.69%, significantly outperforming traditional inhibitors like KCl and NW-1. (2) Under conditions of 140 °C, the cuttings rolling recovery rate of TIL-NH2 reached 88.12%, demonstrating excellent high-temperature resistance. (3) Permeability recovery experiments showed that at a concentration of 2.0 wt%, TIL-NH2 achieved a permeability recovery rate of 90.58%, effectively mitigating formation damage. (4) Dynamic adsorption experiments indicated that at a concentration of 2.5 wt%, the adsorption capacity tended toward saturation, reaching 26.00 mg/g, demonstrating stable adsorption capability. Additionally, environmental friendliness evaluations revealed that TIL-NH2 has a degradation rate exceeding 90% within 28 days, and its acute toxicity is significantly lower than that of traditional inhibitors like KCl (the LC50 of TIL-NH2 is 1080.3 mg/L, whereas KCl is only 385.4 mg/L). This research provides a high-efficiency and environmentally friendly new inhibitor for green drilling fluid systems in horizontal shale gas wells, offering important references for technological advancements in unconventional energy development. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) is a malignant tumor associated with significant rates of morbidity and mortality. Hence, developing efficient predictive models and directing clinical interventions in GC is crucial. Lactylation of proteins is detected in gastric cancer tumors and is linked to the advancement of gastric cancer. Methods: The The Cancer Genome Atlas (TCGA) was utilized to analyze the gene expression levels associated with lactylation. A genetic pattern linked to lactylation was created using Univariate Cox regression and least absolute shrinkage and selection operator (LASSO) regression. The predictive ability of the model was evaluated and confirmed in the Gene Expression Omnibus (GEO) cohort, where patients were divided into two risk groups based on their scores. The study examined the relationship between gene expression and the presence of immune cells in the context of immunotherapy treatment. In vitro cytotoxicity assays, ELISA and PD-1 and PD-L1interaction assays were used to assess the expression of PD-L1 while knocking down SLC16A7. Results: 29 predictive lactylation-related genes with differential expression were discovered. A signature consisting of three genes was developed and confirmed. Patients who had higher risk scores experienced worse clinical results. The group with lower risk showed increased Tumor Immune Dysfunction and Exclusion (TIDE) score and greater responsiveness to immunotherapy. The tumor tissues secrete more lactate acid than normal tissues and express more PD-L1 than normal tissues, that is, lactate acid promotes the immune evasion of tumor cells. In GC, the lactylation-related signature showed strong predictive accuracy. Utilizing both anti-lactylation and anti-PD-L1 may prove to be an effective approach for treating GC in clinical settings. We further proved that one of the lactate metabolism related genes, SCL16A7 could promote the expression of PD-L1 in GC cells. Conclusion: The risk model not only provides a basis for better prognosis in GC patients, but also is a potential prognostic indicator to distinguish the molecular and immune characteristics, and the response from Immune checkpoint inhibitors (ICI) therapy and chemotherapy in GC. [ABSTRACT FROM AUTHOR]

Chemoimmunotherapy, which integrates chemotherapeutic drugs with immune modulators, has emerged as a promising approach to enhance the generally lackluster clinical outcomes of immunotherapy. Nevertheless, a significant challenge lies in orchestrating multiple events associated with diverse mechanisms that activate antitumor immune responses. Here, a novel approach utilizing dual‐responsive covalent organic frameworks (COFs) co‐encapsulating doxorubicin (DOX) and programmed cell death ligand‐1 (PD‐L1) siRNA (siPD‐L1), termed RDAP, is presented for synergistic chemoimmunotherapy. In this system, COFs modified with poly‐L‐lysine (PLL) can adsorb DOX within their porous structure and bind siPD‐L1 onto their surface via electrostatic interactions. The resulting RDAP formulation can escape from lysosome via the "proton sponge effect" and undergo rupture upon exposure to azoreductase, leading to the efficient release of DOX and siPD‐L1 into the cytoplasm of 4T1 cells. The RDAP, harboring dual therapeutic agents, can effectively eliminate tumor cells and trigger significant immunogenic cell death (ICD) through DOX. Additionally, it concomitantly suppresses PD‐L1 expression in tumor cells, thereby significantly enhancing the antitumor immune response and resulting in synergistically improved antitumor efficacy. In mouse models, RDAP demonstrated exceptional efficacy in eliminating both primary and distant tumors, along with a pronounced antimetastatic effect against 4T1 murine breast‐to‐lung metastasis. [ABSTRACT FROM AUTHOR]

The regulation of glial cell activation is a critical step for the treatment or prevention of neuroinflammation‐based brain diseases. However, the development of therapeutic drugs that pass the blood–brain barrier (BBB) and inhibit the glia cell activation remains a significant challenge. Herein, an ultrasmall 2D vanadium carbide quantum dots (V2C QDs) that are capable of crossing the BBB are prepared, and the admirable anti‐neuroinflammatory effects are presented. The prepared 2D V2C QDs with an average size of 2.54 nm show good hydrophilicity, physiological stability, and effective BBB‐crossing ability. The biological effect of V2C QDs on inflammatory reactions demonstrates fascinating results in preventing the impairment of learning and memory in BALB/c mice stimulated by lipopolysaccharide. Investigation of molecular mechanism reveals that V2C QDs not only inhibit the toll‐like receptor 4/myeloid differentiation factor 88‐mediated nuclear factor kappa B and mitogen‐activated protein kinase pathways, but also prevent eukaryotic translation initiation factor 2α/activating transcription factor 4/C/EBP homologous protein‐signaling pathway and reduce oxidative stress via activating the NF‐E2‐related factor‐2/heme oxygenase‐1‐signaling pathway, leading to greatly inhibited activation of microglia and astrocytes and weakened production of inflammatory cytokines. In summary, V2C QDs exert potent anti‐inflammatory effects through multiple pathways, thus offer great potential for the treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

With the development of high spatial resolution spin image and magnetic field distribution measurement in atomic vapor cell, one can localize the position and calculate the magnetic moment of the field source around the cell. However, traditional cubic or spherical vapor cell can only measure the magnetic field distribution on one side of the field source, which limits the precision of the field inversion results. Here, we use a recessed atomic vapor cell to obtain field distribution around the source, which is positioned at the center of the cell. The magnetic field distributions around five sides of the field source are measured using movable stages and digital micro-mirror device. We combine the Levenberg–Marquardt algorithm with a genetic algorithm as the magnetic source localization algorithm to realize a quick global search as well as a precise local extreme point search. We obtain a spatial resolution of 219.2 × 387.0 × 451.5 μ m 3 and a magnetic field sensitivity of 0.06 nT / Hz 1 / 2 in a volume pixel of 0.0383 mm 3. The error in the localization of the magnetic source is 1.295 mm in the x direction, 185 μ m in the y direction, and 40 μ m in the z direction. The field distribution measurement method using recessed atomic vapor cell and related inversion algorithm demonstrated here have great potential applications in small scale field source detection of biology and materials science. [ABSTRACT FROM AUTHOR]