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Hydrogen peroxide (H2O2) and glutathione (GSH) have been reported to be associated with a variety of diseases. Therefore, the accurate and rapid determination of H2O2 and GSH was very important. The traditional assay was the colorimetric method, which suffered from the bottleneck of single-mode analysis. In this work, we designed a dual-mode fluorescence and colorimetric sensor for detecting H2O2 and GSH based on bifunctional Fe, Co-CDs, which possessed peroxidase (POD)-mimetic activity and fluorescence property. Concretely, the Fe, Co-CDs catalyzed oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to a blue product (oxTMB) with the help of H2O2, which could be inhibited by GSH. Meanwhile, the fluorescence of Fe, Co-CDs weakened with increasing oxTMB, realizing the fluorescence analysis of H2O2 and GSH. In fluorescence and colorimetric sensors, the detection limit (LOD) of H2O2 could reach as low as 0.54 μM and 0.81 μM, as well as the LOD of GSH was 0.39 and 0.61 μM, respectively. Besides, the smartphone-assisted hydrogel sensor was developed for on-site detection of GSH via color change. This study not only designed a dual-mode sensor for dual-target detection but also provided insights for further exploration of multifunctional nanozymes. [ABSTRACT FROM AUTHOR]

To optimize thermophysical performances, Sm3TaO7 was doped with Lu3+ and pressureless sintered at 1600 °C. It was shown that Sm3+ is partly substituted by Lu3+ cations and the (Sm1-xLux)3TaO7 ceramics with a single pyrochlore structure are obtained.With increasing x value from 0 to 0.5, the band gap increases gradually from 4.677 to 4.880 eV. Owing to the enhanced phonon scattering caused by Lu3+ doping, the thermal conductivities at 800 °C of the prepared samples are in the range of 0.95-1.44W•K−1•m−1. It was also confirmed that the phase transition is restrained effectively by substituting Sm3+ with Lu3+. Due to the reduction of crystal lattice energy and average electro-negativity difference, the thermal expansion coefficient (TEC) is heightened with increasing Lu content. TEC achieves the highest value (10.45 × 10−6 K−1 at 1200 °C) at the equal molar ratio between Sm3+ and Lu3+ cations (i.e. x = 0.5), which is much higher than those of 7YSZ and Sm2Zr2O7 ceramics.

A dual-mode sensor was developed for detecting acetylcholinesterase (AChE) and organophosphorus pesticides (OPs) via bifunctional BSA-CeO2 nanoclusters (NCs) with oxidase-mimetic activity and fluorescence property. The dual-mode sensor has the characteristics of self-calibration and self-verification, meeting the needs of different detection conditions and provide more accurate results. The colorimetric sensor and fluorescence sensor have been successfully used for detecting AChE with limit of detection (LOD) of 0.081 mU/mL and 0.056 mU/mL, respectively, while the LOD for OPs were 0.9 ng/mL and 0.78 ng/mL, respectively. The recovery of AChE was 93.9–107.2% and of OPs was 95.8–105.0% in actual samples. A novel strategy was developed to monitor pesticide residues and detect AChE level, which will motivate future work to explore the potential applications of multifunctional nanozymes. [ABSTRACT FROM AUTHOR]

The prevalence of cardiovascular disease (CVD) has been rising due to sedentary lifestyles and unhealthy dietary patterns. Peroxisome proliferator‐activated receptor α (PPARα) is a nuclear receptor regulating multiple biological processes, such as lipid metabolism and inflammatory response critical to cardiovascular homeostasis. Healthy endothelial cells (ECs) lining the lumen of blood vessels maintains vascular homeostasis, where endothelial dysfunction associated with increased oxidative stress and inflammation triggers the pathogenesis of CVD. PPARα activation decreases endothelial inflammation and senescence, contributing to improved vascular function and reduced risk of atherosclerosis. Phenotypic switch and inflammation of vascular smooth muscle cells (VSMCs) exacerbate vascular dysfunction and atherogenesis, in which PPARα activation improves VSMC homeostasis. Different immune cells participate in the progression of vascular inflammation and atherosclerosis. PPARα in immune cells plays a critical role in immunological events, such as monocyte/macrophage adhesion and infiltration, macrophage polarization, dendritic cell (DC) embedment, T cell activation, and B cell differentiation. Cardiomyocyte dysfunction, a major risk factor for heart failure, can also be alleviated by PPARα activation through maintaining cardiac mitochondrial stability and inhibiting cardiac lipid accumulation, oxidative stress, inflammation, and fibrosis. This review discusses the current understanding and future perspectives on the role of PPARα in the regulation of the cardiovascular system as well as the clinical application of PPARα ligands. [ABSTRACT FROM AUTHOR]