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Metal organophosphonates have been explored in energy-related fields due to their high chemical and thermal stability as a type of uniformly precursor, but only few of pristine metal organophosphonate are directly used for oxygen evolution reaction (OER) catalysts. Here, a mixed-valence iron phosphonate (Fe3-ppat) has been constructed and applied to OER catalysis considered the potential active sites in pillars FeII(H2O)4(COO)2 and inorganic layers FeIII(μ2–OH)PO3. Specifically, isostructural trimetallic framework Fe1.7Co0.3Ni1.0-ppat possesses a minimum overpotential (291 mV), small Tafel slope (91.65 mV dec−1), and high stability up to 83 h. The enhanced catalytic performance could be mainly ascribed to the synergistic effect of NiII equivalent occupancy in pillars and Co/FeIII in layers.

Doping alkali metal atoms, especially lithium (Li), in nanocarbon materials has always been considered to be one of the most effective methods to improve the optical properties of the system. In this theoretical work, we doped a Li atom to the recently observed all-carboatomic molecule, cyclo[18]carbon (C18), and finally obtained two stable configurations with Li inside and outside the ring. The calculation results show that the energy barrier of transition between the two Li@C18 configurations is low, so the conversion is easy to occur at ambient temperature. Further study reveals that the state of Li@C18 complex, namely its dominant configuration, can be switched by applying a proper external electric field (EEF). The electronic structure, absorption spectrum, and optical nonlinearity of the two configurations are found to be significantly different, which indicates that the optical properties of the Li@C18 complex can be effectively regulated by switching the location of doped Li atom between inside and outside the carbon ring. With the help of various wavefunction analysis methods, the nature of the discrepancies in the properties of Li@C18 complex with different configurations was deeply revealed. The relevant results are expected to provide theoretical guidance for development of cyclocarbon-based optical molecular switches.

Calreticulin (Crt) is a highly conserved and multi-functional protein with lectin-like properties and important immunological activities. In this study, a Crt homolog, namely, ToCrt, was cloned and characterized from the obscure puffer Takifugu obscurus with an open reading frame of 1278 bp encoding a putative protein of 425 amino acids. The deduced amino acid sequence of ToCrt consisted of three conserved structural domains: N-domain, P-domain, and C-terminal domain. In the phylogenetic tree, ToCrt formed a separate cluster with three Crts from other pufferfish species (Takifugu rubripes, Takifugu flavidus, and Takifugu bimaculatus). The mRNA transcript of ToCrt was ubiquitously expressed in all the examined tissues in a decreasing order: liver, spleen, kidney, gills, intestine, and heart. After Vibrio harveyi, Edwardsiella tarda, and Aeromonas hydrophila stimulations, the levels of ToCrt mRNA in the kidney and spleen were significantly upregulated compared with that in the control group. The recombinant calreticulin domain of ToCrt (rToCrt) could bind three Gram-negative bacteria (V. harveyi, E. tarda, and A. hydrophila) and polysaccharides from bacterial cell walls such as lipopolysaccharide and peptidoglycan. Meanwhile, rToCrt could agglutinate different kinds of microorganisms and exhibit antimicrobial activity. These results suggested that T. obscurus ToCrt could serve as an antimicrobial effector in the host immune response against invading microorganisms.

Methods to detect and quantify disease biomarkers with high specificity and sensitivity in biological fluids play a key role in enabling clinical diagnosis, including point-of-care testing. Myeloperoxidase (MPO) is an emerging biomarker for the detection of inflammation, neurodegenerative diseases, and cardiovascular disease, where excess MPO can lead to oxidative damage to biomolecules in homeostatic systems. While numerous methods have been developed for MPO analysis, most techniques are challenging in clinical applications due to the lack of amplification methods, high cost, or other practical drawbacks. Enzyme-linked immunosorbent assays are currently used for the quantification of MPO in clinical practice, which is often limited by the availability of antibodies with high affinity and specificity and the significant nonspecific binding of antibodies to the analytical surface. In contrast, nucleic acid-based biosensors are of interest because of their simplicity, fast response time, low cost, high sensitivity, and low background signal, but detection targets are limited to nucleic acids and non-nucleic acid biomarkers are rare. Recent studies reveal that the modification of a genome in the form of phosphorothioate is specifically sensitive to the oxidative effects of the MPO/H2O2/Cl- system. We developed an oxidative cleavage-based three-dimensional DNA biosensor for rapid, ratiometric detection of HOCl and MPO in a "one-pot" method, which is simple, stable, sensitive, specific, and time-saving and does not require a complex reaction process, such as PCR and enzyme involvement. The constructed biosensor has also been successfully used for MPO detection in complex samples. This strategy is therefore of great value in disease diagnosis and biomedical research.

A key objective for herbicide research is to develop new compounds with improved bioactivity. Protoporphyrinogen IX oxidase (PPO) is an essential target for herbicide discovery. Here, we report using an in silico structure-guided optimization approach of our previous lead compound 1 and designed and synthesized a new series of compounds 2-6. Systematic bioassays led to the discovery of a highly potent compound 6g, 1-methyl-3-(2,2,7-trifluoro-3-oxo-4-(prop-2-yn-1-yl)-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione, which exhibited an excellent and wide spectrum of weed control at the rates of 30-75 g ai/ha by the postemergence application and is relatively safe on maize at 75 g ai/ha. Additionally, the Ki value of 6g to Nicotiana tabacum PPO (NtPPO) was found to be 2.5 nM, showing 3-, 12-, and 18-fold higher potency relative to compound 1 (Ki = 7.4 nM), trifludimoxazin (Ki = 31 nM), and flumioxazin (Ki = 46 nM), respectively. Furthermore, molecular simulations further suggested that the thieno[2,3-d]pyrimidine-2,4-dione moiety of 6g could form a more favorable π-π stacking interaction with the Phe392 of NtPPO than the heterocyclic moiety of compound 1. This study provides an effective strategy to obtain enzyme inhibitors with improved performance through molecular simulation and structure-guided optimization.

There are several natural materials which have evolved functional gradients, ingeniously attaining maximal efficacy from limited components. Herein, we utilized the spatiotemporal distribution of initiator acetylacetone to regulate the multienzyme polymerization and fabricate a chitosan-polymer hydrogel. The temporal priority order of acetylacetone was higher than phenol-modified chitosan by density functional theory calculation. The acetylacetone within the gelatin could gradually diffuse spatially into the chitosan hydrogel to fabricate the composite hydrogel with gradient network structure. The gradient hydrogel possessed a transferring topography from the two-dimensional pattern. A continuously decreased modulus along with acetylacetone diffusion was confirmed by atomic force microscope-based force mapping experiment. The water-retaining ability of various regions was confirmed by low-field nuclear magnetic resonance (NMR) and thermogravimetric analysis (TG) analysis, which led to the spontaneous actuation of gradient hydrogel with maximum 1821°/h curling speed and 227° curling angle. Consequently, the promising gradient hydrogels could be applied as intelligent actuators and flexible robots.

Circadian rhythm disorder (CRD) in space flight can lead to memory impairment, performance decrements and adverse health outcomes, the main manifestations of which are circadian desynchronization, sleep loss and insomnia. Sleep deprivation (SD) provide the means to evaluate these effects and the risks associated with CRD on ground. Gastrodia elata Blume (GEB) has beneficial effects on the treatment of sleep disturbances and memory loss. Fresh GEB (FG), an unprocessed raw tuber of GEB, has been used as functional health food in Asian countries for a long time. However, the research report of FG to ameliorate memory impairment caused by insomnia or lack of sleep is meager. In this study, ICR male mice were sleep-deprived continuously and water extract of FG (WFG) was orally administrated (3 and 9 g/kg/d, i.g) during the SD process lasted for 25 days, except control and model groups gavage administration with water, positive control group with modafinil (MOD, 0.1 g/kg/d, i.g). We studied the effect of WFG on CRD-induced learning and memory impairment using a set of behavioral analyses including the object location recognition test (OLRT), novel object recognition test (NORT), and the passive avoidance test (PAT). In addition, oxidative stress parameters were assessed by measuring the malondialdehyde (MDA) and superoxide dismutase (SOD) reactivity in serum and hippocampus. Our results revealed that SD decreased discrimination index (DI) in OLRT and NORT, with shorter latency into the dark chamber in PAT. Both WFG and MOD treatment can reverse these changes (P0.05). We concluded that WFG treatment improve CRD-induced learning and memory impairment and oxidative stress damage which makes FG a promising candidate as herbal health product of memory decline in CRD.

Succinate dehydrogenase (SDH, EC 1.3.5.1) has proven to be an important fungicidal target, and the inhibition of SDH is useful in the treatment of plant pathogens. The discovery of a novel active SDH inhibitor is of high value. Herein, we disclose the discovery of a potent, highly active inhibitor as a fungicide candidate by using a computational substitution optimization method, a fast drug design method developed in our laboratory. The greenhouse experiments showed that compound 17c exhibited high protective activity against south corn rust, soybean rust (SBR), and rice sheath blight at a very low dosage of 0.781 mg/L. Moreover, the field trials indicated that compound 17c is comparable to and even better than commercial fungicides against SBR and cucumber powdery mildew at 50 mg/L concentration. Most surprisingly, compound 17c resulted to be strictly better in curative activity than the commercial fungicide benzovindiflupyr. The computation results indicated that 17c could form another hydrogen bond with C_S42 and then lead to strong van der Waals and electronic interactions with SDH. Our results suggested that 17c is a potential fungicide candidate for SDH.

HSCCC was widely used as a reliable and efficient tool for isolation of natural production. Multiple active compounds were separated and purified from ginger essential oil. But the remaining ginger powder (RGP), which was obtained from ginger without volatile oil, was discarded commonly. The crude flavonoids were extracted from RGP using ethanol at 80°C. The purification of flavonoids was performed by rotary evaporator and X-5 macroporous adsorption resin. The high-speed counter-current chromatography (HSCCC) was implemented by employing a two-phase solvent system which consist of n-hexane–ethyl acetate–methanol-water (4:5:4:5, v/v/v/v) and n-hexane–ethyl acetate–methanol-water (1:5:1:5, v/v/v/v) to separate flavonoid into five fractions. The purity of individual flavonoid in each of the fraction was analyzed by high-performance liquid chromatography (HPLC). The chemical structures of the isolated compounds were identified by liquid chromatograph mass spectrometry-ion trap-time of flight (LCMS-IT-TOF). Rutin (16.6%), tangeretin (13.1%), vitexin (18.37%), myricetin-3-O-glucopyranoside (3.3%), and isoquercitrin (15.2%) were identified in RGP at the purity of all over 90%. The HSCCC appeared to be an efficient and reliable method for the isolation of flavonoids in RGP. 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to determine the anti-tumor abilities of five flavonoid compounds. The results showed that rutin and myricetin-3-O-glucopyranoside had better anti-tumor activities than other three flavonoid compounds from RGP. The research revealed that RGP was a bioactive product and contributed to development of ginger.

As a crucial biomarker for some diseases, the determination of cholesterol in human serum is of great significance for the diagnosis and prevention of these diseases. Hence, a portable cholesterol detection method is necessary for clinical and domestic applications. Here, a portable paper sensor was designed for cholesterol detection by modifying screen-printed electrode (SPE) with nanoporous gold (NPG). To achieve the reliable cholesterol detection, a synergistic strategy was proposed based on the oxidation of cholesterol by cholesterol oxidase (ChOx) and the reduction of oxidation product (H2O2) by NPG. Compared to existing electrochemical sensors, the resulting paper sensor exhibited a wider linear response in a range from 50 μM to 6 mM as well as a higher sensitivity of 32.68 μA mM−1 cm−2 with a lower detection limit of 8.36 μM. Moreover, the portable paper sensor presented strong anti-interference capability and stability in the detection of cholesterol in human serum, and the data detected by the portable paper sensor were consistent with that obtained by an automatic biochemical analyzer. These unique performances confirmed that the proposed paper sensor was a sensitive, reliable, and portable cholesterol detection method, making it a good choice for cholesterol detection.

Multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19) has been described to partially overlap with Kawasaki disease (KD) with regard to clinical symptoms, but they are unlikely to share the same disease entity. We conducted a systematic review and meta-analysis to characterize the laboratory parameters of MIS-C compared with those of KD and Kawasaki disease shock syndrome (KDSS). Databases were searched for studies on laboratory parameters of MIS-C (hematology, inflammatory markers, cardiac markers, and biochemistry) through May 31, 2021. Twelve studies with 3073 participants yielded 969 MIS-C patients. In terms of hematology, MIS-C patients had lower levels of leukocytes, absolute lymphocyte count and platelet count (PLT) than KD patients and had similar absolute neutrophil count (ANC) and hemoglobin (Hb) levels. In terms of inflammatory markers, MIS-C patients had higher levels of C-reactive protein, D-dimer and ferritin than KD patients and had similar levels of procalcitonin and erythrocyte sedimentation rate (ESR). In terms of cardiac markers, MIS-C patients had higher CPK levels than KD patients. The levels of N-terminal pro-brain natriuretic peptide, troponin and aspartate aminotransferase were not significantly different between MIS-C and KD patients. In terms of biochemistry, MIS-C patients had lower levels of albumin, sodium and alanine aminotransferase and higher levels of creatinine than KD patients. In addition, MIS-C patients had lower levels of PLT, Hb and ESR and higher levels of ANC than KDSS patients. Measurement of laboratory parameters might assist clinicians with accurate evaluation of MIS-C and further mechanistic research.

Calcyphosine (CAPS) was initially identified from the canine thyroid. It also exists in many types of tumor, but its expression and function in glioma remain unknown. Here we explored the clinical significance and the functional mechanisms of CAPS in glioma. We found that CAPS was highly expressed in glioma and high expression of CAPS was correlated with poor survival, in glioma patients and public databases. Cox regression analysis showed that CAPS was an independent prognostic factor for glioma patients. Knockdown of CAPS suppressed the proliferation, whereas overexpression of CAPS promoted the proliferation of glioma both in vitro and in vivo. CAPS regulated the G2/M phase transition of the cell cycle, but had no obvious effect on apoptosis. CAPS affected PLK1 phosphorylation through interaction with MYPT1. CAPS knockdown decreased p-MYPT1 at S507 and p-PLK1 at S210. Expression of MYPT1 S507 phosphomimic rescued PLK1 phosphorylation and the phenotype caused by CAPS knockdown. The PLK1 inhibitor volasertib enhanced the therapeutic effect of temozolomide in glioma. Our data suggest that CAPS promotes the proliferation of glioma by regulating the cell cycle and the PLK1 inhibitor volasertib might be a chemosensitizer of glioma. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

BACKGROUND Different thermoplastic starch (TPS) films were prepared with or without the addition of microcrystalline cellulose (MCC) obtained via the melt-extrusion method, and then the hot-press method was used to produce environmentally friendly TPS-based film/paper composites to replace petroleum-based materials. RESULTS The paper-plastic composites exhibited good interfacial adhesion from the scannign elctron microscopy images. It was seen that 5 wt.% MCC was added to reinforce the mechanical properties of TPS films, such that it also improved the barrier properties of MCC@TPS/paper composites and extended the path of water vapor through TPS films, which decreased the water vapor transmission rate of MCC@TPS/paper composites. TPS/paper composites and MCC@TPS/paper composites have better physical properties (i.e. smoothness, flexibility and folding resistance) than only paper. In particular, it was found that the water contact angle of MCC@TPS/paper composites and TPS/paper composites were higher than single-layer paper. Furthermore, MCC reinforced paper-plastic composites demonstrated good barrier properties which can meet the requirement of the need for lower water sensitive materials in the food packaging industry. CONCLUSION Thermoplastic corn starch-based film/paper composites have good application properties as a potential source of bioplastic materials. © 2021 Society of Chemical Industry.

The purpose of this study is to investigate thermodynamic and kinetic properties on the hydrogen-atom-donating ability of 4-substituted Hantzsch ester radical cations (XRH•+), which are excellent NADH coenzyme models. Gibbs free energy changes and activation free energies of 17 XRH•+ releasing H• [denoted as ΔGHDo(XRH•+) and ΔGHD≠(XRH•+)] were calculated using density functional theory (DFT) and compared with that of Hantzsch ester (HEH2) and NADH. ΔGHDo(XRH•+) range from 19.35 to 31.25 kcal/mol, significantly lower than that of common antioxidants (such as ascorbic acid, BHT, the NADH coenzyme, and so forth). ΔGHD≠(XRH•+) range from 29.81 to 39.00 kcal/mol, indicating that XRH•+ spontaneously releasing H• are extremely slow unless catalysts or active intermediate radicals exist. According to the computed data, it can be inferred that the Gibbs free energies and activation free energies of the core 1,4-dihydropyridine radical cation structure (DPH•+) releasing H• [ΔGHDo(DPH•+) and ΔGHD≠(DPH•+)] should be 19–32 kcal/mol and 29–39 kcal/mol in acetonitrile, respectively. The correlations between the thermodynamic driving force [ΔGHDo(XRH•+)] and the activation free energy [ΔGHD≠(XRH•+)] are also explored. Gibbs free energy is the important and decisive parameter, and ΔGHD≠(XRH•+) increases in company with the increase of ΔGHDo(XRH•+), but no simple linear correlations are found. Even though all XRH•+ are judged as excellent antioxidants from the thermodynamic view, the computed data indicate that whether XRH•+ is an excellent antioxidant in reaction is decided by the R substituents in 4-position. XRH•+ with nonaromatic substituents tend to release R• instead of H• to quench radicals. XRH•+ with aromatic substituents tend to release H• and be used as antioxidants, but not all aromatic substituted Hantzsch esters are excellent antioxidants.

The increasing demand to develop sustainable energy storage equipment has aroused interest for potassium-ion capacitors (PICs), owing to their high abundance and low cost of potassium sources. Nevertheless, the practical application of PICs is impeded by the lack of suitable anode materials with high performance. Here we demonstrate a solvothermal-assisted synthesis of porous CoV2O6 nanosphere@graphene oxide (GO) composites as the anode material of PICs for the first time. Benefiting from the well-designed porous nanostructure and high-conductivity carbon incorporation, the hybrid composite delivers an initial high discharge capacity (264 mAh g−1, 1 A g−1) and superior rate capability (97 mAh g−1, 10 A g−1). Moreover, the electrochemical reaction mechanism of CoV2O6 involving an intercalation followed by conversion reaction is comprehensively revealed by first-principles calculations (DFT), ex-situ X-ray photoelectron spectroscopy as well as ex-situ high-resolution transmission electron microscopy. Meanwhile, the DFT also indicates that CoV2O6 possesses high electron/K-ion conductivity and low diffusion barriers for K+ intercalation. Consequently, PICs coupling the CoV2O6@GO anode and activated carbon cathode display a high energy/power density (78.2 Wh kg−1 and 22,500 W kg−1) as well as an ultralong lifespan over 3000 cycles. The work delves metal vanadate as high-performance anode for PICs and may provide innovative insight into electrode structure building in rechargeable metal-ions chemistry.

Peroxisome proliferator-activated receptor α (PPARα), a ligand-activated nuclear receptor critical for systemic lipid homeostasis, has been shown closely related to cardiac remodeling. However, the roles of cardiomyocyte PPARα in pressure overload-induced cardiac remodeling remains unclear because of lacking a cardiomyocyte-specific Ppara-deficient (Ppara(ΔCM)) mouse model. This study aimed to determine the specific role of cardiomyocyte PPARα in transverse aortic constriction (TAC)-induced cardiac remodeling using an inducible Ppara(ΔCM) mouse model. Ppara(ΔCM) and Ppara(fl/fl) mice were randomly subjected to sham or TAC for 2 weeks. Cardiomyocyte PPARα deficiency accelerated TAC-induced cardiac hypertrophy and fibrosis. Transcriptome analysis showed that genes related to fatty acid metabolism were dramatically downregulated, but genes critical for glycolysis were markedly upregulated in Ppara(ΔCM) hearts. Moreover, the hypertrophy-related genes, including genes involved in extracellular matrix (ECM) remodeling, cell adhesion, and cell migration, were upregulated in hypertrophic Ppara(ΔCM) hearts. Western blot analyses demonstrated an increased HIF1α protein level in hypertrophic Ppara(ΔCM) hearts. PET/CT analyses showed an enhanced glucose uptake in hypertrophic Ppara(ΔCM) hearts. Bioenergetic analyses further revealed that both basal and maximal oxygen consumption rates and ATP production were significantly increased in hypertrophic Ppara(fl/fl) hearts; however, these increases were markedly blunted in Ppara(ΔCM) hearts. In contrast, hypertrophic Ppara(ΔCM) hearts exhibited enhanced extracellular acidification rate (ECAR) capacity, as reflected by increased basal ECAR and glycolysis but decreased glycolytic reserve. These results suggest that cardiomyocyte PPARα is crucial for the homeostasis of both energy metabolism and ECM during TAC-induced cardiac remodeling, thus providing new insights into potential therapeutics of cardiac remodeling-related diseases.

N6-methyladenosine (m6A) is the most prevalent RNA epigenetic regulator in cancer. However, the understanding of m6A modification on lipid metabolism regulation in colorectal cancer (CRC) is very limited. Here, we observed that human CRCs exhibited increased m6A mRNA methylation mediated by dysregulation of m6A erasers and readers. By performing methylated RNA-immunoprecipitation sequencing (MeRIP-seq) and transcriptomic sequencing (RNA-seq), we identified DEGS2 as a downstream target of m6A dysregulation. Overexpression or knockdown of DEGS2 confirmed the role of DEGS2 in proliferation, invasion and metastasis of CRC both in vitro and in vivo. Mechanistic studies identified the specific m6A modification site within DEGS2 mRNA, and mutation of this target site was found to drastically enhance the proliferative and invasive ability of CRC cells in vitro and promote tumorigenicity in vivo. Lipidome analysis showed that lipid metabolism was dysregulated in CRC. Moreover, ceramide synthesis was suppressed due to DEGS2 upregulation mediated by m6A modification in CRC tissues. Our findings highlight that the function of DEGS2 m6A methylation in CRC and extend the understanding of the importance of RNA epigenetics in cancer biology.

A new strategy for the determination of picolinic acid (PLA) is developed by utilizing green-emissive boron and nitrogen co-doped carbon nanodots (BNCNDs) and Cu2+ ion. Hydroquinone, uric acid and boric acid act as carbon, nitrogen and boron sources for BNCNDs synthesis, respectively. Interestingly, the green emission of BNCNDs is quenched in the presence of Cu2+ by electron transfer. Upon addition of the specific reagent (PLA), Cu2+ ion is removed from the surface of BNCNDs owing to the formation of a strong complex between PLA and Cu2+ ion, which leads to a significant fluorescence recovery of BNCNDs. The “turn-on” phenomenon allows to determine PLA by a very simple method. This chemosensing method displays a linear range from 50 nM to 80 μM with a detection limit of 14 nM (3σ/k) for PLA. The method was applied to the determination of PLA in fetal bovine serum samples with the recoveries between 94 and 106%, which shows that this method has potential for use in applications to real samples.

Interlayer coupling as a unique feature for two-dimensional (2D) materials may influence their thickness-dependent physical properties, especially the bandgap due to quantum confinement effect. Widely-studied 2D materials usually possess strong interlayer coupling such as most of transition metal dichalcogenides (TMDs), PtS2 and so on. However, 2D materials with weak interlayer coupling are rarely referred that mainly focus on ReS2, as well as its counterpart ReSe2. Here we report a new member of weak interlayer coupling 2D materials, germanium disulfide (GeS2). The interlayer interaction in GeS2 is investigated from theory to experiment. By density functional theory calculations, we find that this extraordinarily weak interlayer coupling in GeS2 originates from the weak hybridization of interlayer S atoms. Thickness-dependent Raman spectra of GeS2 flakes exhibit that the Raman peaks remain unchanged when increasing the thickness; and a small first-order temperature coefficient of −0.00857 cm−1·K−1 is obtained from the temperature-dependent Raman spectra. These experimental results further confirm the weak interlayer coupling in GeS2.

Aryl bromide is one of the most important compounds in organic chemistry, because it is widely used as synthetic building blocks enabling quick access to a wide array of bioactive molecules, organic materials, and polymers via the versatile cutting-edge transformations of C-Br bond. Direct C-H bond functionalization of aryl bromide is considered to be an efficient way to prepare functionalized aryl bromides; however, it is rarely explored possibly due to the relatively low reactivity of aryl bromide toward C-H bond activation. We herein report a palladium-catalyzed coupling reaction between aryl iodide and aryl bromide for preparing brominated biaryl compounds via a silver-mediated C-H bond activation pathway.

The self-assembled phospholipid- or cytosol-associated multienzyme complexes constitute necessary components of the foundation of life. As a proof of concept, metal-coordinated supramolecular nanogels (MCSGs) have been designed, with the self-assembly of di-lysine coordinated iron (Fe(Lys)2)-functionalized peptide gelators on the interface by an in situ amidation-induced protonation process. The monoatomic and highly dispersed active centers of Fe(Lys)2 offered the nanogel mimics with excellent reaction rates due to the high density and nano compartmental structure similar to the natural matrix-associated multienzyme complex. SiO2@MCSGs show both superoxide dismutase (SOD) activity and peroxidase (POD) activity, and the higher activities compared with the activity of free Fe(Lys)2 molecules can be detected. After loading the substrate 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS), SiO2@MCSGsABTS can responsively convert O2− · in the tumor microenvironment into H2O2 intermediates and then tandem catalyzed the oxidization of ABTS for contrast photoacoustic (PA) imaging of tumor by the SOD-POD mimic activity, showing their great potential as the efficient enzymatic agents for pathological theranostics.

Urotensin II (UII) is involved in the formation of atherosclerosis, but its role in the stability of atherosclerotic plaques is unknown. The purpose of this study was to observe the dynamic changes in plasma UII and analyze its relationship to the stability of atherosclerotic plaques. One hundred thirty-five consecutive patients with acute coronary syndrome (ACS) were enrolled. The plasma UII levels were measured immediately after admission and during three-month follow-up. A vulnerable plaque model was established using local transfection of a recombinant P53 adenovirus into plaques in rabbits fed with a high-cholesterol diet and subjected to balloon arterial injury. The levels of plasma UII were measured weekly. The changes in plasma UII during the formation of atherosclerotic plaques and before and after plaque transfection were observed. The morphology of the plaques and the expression, distribution, and quantitative expression of UII in the plaques also were observed. Our results showed that the levels of plasma UII in patients with ACS at admission were lower than levels observed at the three-month follow-up. UII dynamic changes and its correlation with plaque stabilities were further verified in rabbits with atherosclerotic vulnerable plaques. The UII levels in rabbits were significantly decreased immediately after the P53 gene transfection, which led to plaque instability and rupture. These results suggested that UII expression was down-regulated in ACS, which may be related to its ability to modulate mechanisms involved in plaque stability and instability.

The extracellular contractile injection systems (eCISs) are encoded in the genomes of a large number of bacteria and archaea. We have previously characterized the overall structure of Photorhabdus Virulence Cassette (PVC), a typical member of the eCIS family. PVC resembles the contractile tail of bacteriophages and exerts its action by the contraction of outer sheath and injection of inner tube plus central spike. Nevertheless, the biological function of PVC effectors and the mechanism of effector translocation are still lacking. By combining cryo-electron microscopy and functional experiments, here we show that the PVC effectors Pdp1 (a new family of widespread dNTP pyrophosphatase effector in eCIS) and Pnf (a deamidase effector) are loaded inside the inner tube lumen in a "Peas in the Pod" mode. Moreover, we observe that Pdp1 and Pnf can be directly injected into J774A.1 murine macrophage and kill the target cells by disrupting the dNTP pools and actin cytoskeleton formation, respectively. Our results provide direct evidence of how PVC cargoes are loaded and delivered directly into mammalian macrophages.

N-acetyl-L-cysteine-modified CdTe QDs (Cadmium Telluride Quantum Dots) were obtained by hydrothermal method, and DA (amino deoxyglucose), PEG (polyethylene glycol), and 9-p-D (9 polyamine acid) were obtained by ligand substitution, which were used for remodifying CdTe QDs. Successively, a novel CdTe QDs nanoma-terial, CdTe-NALC, was obtained. This composite nanometer material was characterized by ultraviolet, fluorescence spectrum, nuclear magnetic resonance hydrogen-spectrum, and other methods to study further its biocompatibility and toxic effect on the primary cultured mouse hippocampus neurons. PC12 cells were vitro-cultured and dissolved in the CdTe-NALC solution with different concentrations. After 24 h, the expression levels of proteins related to the cAMP (cyclic adenosine monophosphate)-CREB (cAMP response element-binding proteins)-BDNF (brain-derived neurotrophic factor) signaling pathway in the cells were detected by ELISA (enzyme-linked immunosorbent assay) kit. In the experiment, the DA/9-p-D/PEG-modified CdTe QDs composite nanometer material was successfully manufactured by ligand replacement. The nanoparticles had good dis-persibility with an average particle size of about 9.2 nm. DA/9-p-D/PEG modification improved the biocompatibil-ity of the QDs. CdTe composite nanomaterials could significantly reduce the cell activity of mouse hippocampal neurons and promote their apoptosis, with an evident dose-apoptosis relationship. With the increase of CDTE-NALC solution concentration, cAMP, pCREB (phosphorylated CREB), and BDNF protein content decreased (P < 0.05).

As an interface between the different insulating polymers exists in the joints of High Voltage Direct Current (HVDC) cables, the differences in the field-and-temperature dependence of the conductivities of the materials is regarded as a problem leading to interface charge accumulation and field distortion. In this report, using blocking materials to prevent charge injection from one or both sides of the electrodes, the contributions of charge injection and ionization in low-density polyethylene (LDPE), cross-linked polyethylene with nanoparticles (nano-XLPE) and ethylene propylene diene monomer (EPDM) are distinguished and evaluated based on the results from pulsed electro-acoustic (PEA) method. It is found that the contributions of charge injection and ionization behave differently in different materials. The mechanism behind the field-and-temperature dependences of the conductivities of the three materials is explained successfully. This study helps to clarify the charge transfer mechanism, and thus supports the quantitative calculation of the space charge and electric field distribution in cable joints.

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is an effective target for green herbicide discovery. In this work, we reported the unexpected discovery of a novel series of N-phenylaminomethylthioacetylpyrimidine-2,4-diones (2-6) as promising PPO inhibitors based on investigating the reaction intermediates of our initially designed N-phenyluracil thiazolidinone (1). An efficient one-pot procedure that gave 41 target compounds in good to high yields was developed. Systematic Nicotiana tabacum PPO (NtPPO) inhibitory and herbicidal activity evaluations led to identifying some compounds with improved NtPPO inhibition potency than saflufenacil and good post-emergence herbicidal activity at 37.5-150 g of ai/ha. Among these analogues, ethyl 2-((((2-chloro-4-fluoro-5-(3-methyl-2,6-dioxo-4-(trifluoromethyl)-3,6-dihydropyrimidin-1(2H)-yl)phenyl)amino)methyl)thio)acetate (2c) (Ki = 11 nM), exhibited excellent weed control at 37.5-150 g of ai/ha and was safe for rice at 150 g of ai/ha, indicating that compound 2c has the potential to be developed as a new herbicide for weed management in paddy fields. Additionally, our molecular simulation and metabolism studies showed that the side chains of compound 2c could form a hydrogen-bond-mediated seven-membered ring system; substituting a methyl group at R1 could reinforce the hydrogen bond of the ring system and reduce the metabolic rate of target compounds in planta.

Chiral perovskites have emerged as a significant class of materials showing promising optoelectronic and spintronic applications. Reports of chiral perovskite ferroelectrics, however, have been scarce. In this work, we have successfully synthesized homochiral lead-iodide perovskite ferroelectrics [(R)-N-(1-phenylethyl)ethane-1,2-diaminium]PbI4 and [(S)-N-(1-phenylethyl)ethane-1,2-diaminium]PbI4 by the chemical design of introducing a methyl group into the organic cation of the parent (N-benzylethane-1,2-diaminium)PbI4. Vibrational circular dichroism spectra identify the chiral mirroring relationship. They both undergo 222F2 type paraelectric-ferroelectric behavior at around 378 K coupled with clear ferroelastic domains "ON/OFF" switching. Besides, they exhibit an evident thermochromism with color change from orange-yellow to orange-red. To our knowledge, the discovery of integrated ferroelectricity, ferroelasticity and reversible thermochromism in chiral perovskites is unprecedented. This finding offers a resultful path to design chiral perovskite ferroelectrics and is of great inspiration to the discovery of multifunctional perovskite materials.

Conversion-type NiO material is attractive due to its high theoretical capacity, and yet it displays inadequate reaction sites, a huge volume expansion, and a sluggish ions/electrons’ transport rat...

Sulfamic acid 2-Aminobenzothiazole-6-carboxylic acid functionalized Fe3O4 nanoparticles as a novel organic-inorganic hybrid heterogeneous catalyst were manufactured and characterized by FT-IR, XRD,...

In this paper, a kind of fluorescent anti-counter feiting acrylate pressure-sensitive adhesive (PSA) label was prepared using 7-hydroxycoumarin and acrylate monomer. First,7-hydroxycoumarin was rea...

Determination of Cabernet Sauvignon grapes quality plays an important role in commercial processing. In this research, a rapid approach based on near infrared spectroscopy was proposed to the determination of soluble solids content (SSC), pH, and total phenol content (TPC) in entire bunches of Cabernet Sauvignon grapes. Standardized normal variate (SNV) and competitive adaptive weighted sampling (CARS), genetic algorithm (GA), and synergy interval partial least squares (si-PLS) were used to optimize the spectral data. With optimal combination input, the prediction accuracy of partial least squares regression (PLSR) and support vector regression (SVR) models was compared. The results showed that these models based on variable optimization method could predict well the SSC, pH, and TPC of Cabernet Sauvignon grapes. The correlation coefficient of prediction for SSC, pH, and TPC had reached more than 0.85. This work provides an alternative to analyze the chemical parameters in whole bunch of Cabernet Sauvignon grape.

Background The risk of injury to the kidney can be significantly exacerbated by the presence of tumors and the effects of related treatments. Kidney injury associated with cancer is common in multiple myeloma, tumor lysis syndrome, hematopoietic stem cell therapy, and chemotherapy. Cancer patients are at increased risk of infection, sepsis, tumor lysis syndrome, drug-related toxicity, and other comorbidities, leading to a significantly increased risk of acute kidney injury (AKI). This study retrospectively analyzed the clinical data of AKI in cancer patients and explored the predictive value of Cystatin C (CysC) in the prognosis of cancer patients with AKI. Methods Cancer patients attending the Fifth People's Hospital of Shenyang from April 2014 to March 2019 were enrolled according to inclusion and exclusion criteria. Cancer patients with AKI were divided into two groups according to the changes in renal function during the follow-up period: a renal function recovery group and a nonrecovery group. The differences in baseline data of the two groups were compared. Logistic univariate and multivariate regression analyses were conducted to determine the risk of renal function failure. Results A total of 3,127 cases were included. Among them, 659 cases (21.1%) had AKI, and 2,468 cases had no AKI. Among the 659 AKI patients, 473 (71.8%) patients' renal function recovered, while 186 (28.2%) did not. Logistic univariate and multivariate regression analyses indicated that age [odds ratio (OR) =1.133, 95% confidence interval (CI): 1.064-1.219], diabetes (OR =1.226, 95% CI: 1.093-1.385), chronic kidney disease (CKD) (OR =1.347, 95% CI: 1.108-1.624), hematological malignancies (OR =1.174, 95% CI: 1.063-1.311), chemotherapy (OR =1.119, 95% CI: 1.055-1.304), systolic blood pressure (OR =1.108, 95% CI: 1.062-1.267), serum creatinine (Scr) (OR =1.262, 95% CI: 1.105-1.446), and CysC (OR =1.416, 95% CI: 1.251-1.739) were related to the failure of renal function to recover after AKI. Conclusions Baseline CysC level is associated with the occurrence of AKI in cancer patients and a failure to recover renal function during follow-up.

Traditional oxide transparent conductive materials are very brittle, resulting in greatly reduced optoelectronic performance under bending. An effective solution is embedding flexible conductive materials, such as Ag or Cu, into the ceramic oxides. Here, AZO/Ag multilayers were deposited on glass and polyethylene terephthalate (PET) substrates by magnetron sputtering at room temperature. The influence of the various layered structures (AZO/Ag/AZO, AZO/Ag/AZO/Ag/AZO, or AZO/Ag/AZO/AZO/Ag/AZO) on the optoelectronic properties of the multilayers was investigated. The results show that the resistivity of AZO thin film with an embedded Ag layer is significantly reduced, especially when the Ag layer is thick enough to become continuous. Additionally, the electrical stability of AZO thin film under bending was greatly enhanced when embedded with a continuous Ag layer. The resistance of AZO/Ag/AZO/Ag/AZO five-layer film remained almost unchanged even as the bending angle reached 172°. The results indicate that a multilayer structure of AZO/Ag films has great potential in flexible electrode applications.

This paper presents a detailed theoretical investigation on the interaction between methylmethoxy (CH3OCH2) and nitrogen monoxide (NO) during thermal oxidation of dimethyl ether (DME). The calculated results indicate that the CH3OCH2 + NO reaction proceeds by the addition of N atom of NO to CH3OCH2 radical to generate an energy-rich adduct CH3OCH2NO with no barrier involved on the singlet potential energy surface. Subsequently, the most favored dissociation pathway for the formed CH3OCH2NO is a series of H-transfer processes to produce P1 (CH3OCN + H2O), followed by the decomposition of newly formed CH3OCN to generate P2 (CH2O + HCN + H2O). Formation of P3 (CH2O + CH2NOH) by further dissociation of CH3OCH2NO, with a higher barrier needed to overcome, may have a less yield compared to the CH3OCN + H2O production. Moreover, the direct H-abstraction pathway is also identified to produce P4 (ethylene oxide + HNO), and due to a significantly pronounced barrier, it is much less competitive with the association channel. Because the transition states involved in the most favorable pathway lie almost higher than the initial reactants CH3OCH2 + NO in energy, only at high temperatures the reaction between CH3OCH2 and NO is expected to be important. This work can assist in future experimental investigations on the CH3OCH2 + NO reaction.

Reaction of aryl 2-pyridyl ethers with arylzinc reagents under catalysis of NiCl2(PCy3)2 affords aryl-aryl cross-coupling products via selective cleavage of CAr-OPy bonds. The reaction features a wide substrate range and good compatibility of functional groups. β-H-free alkylzinc reagents are also applicable as the nucleophiles in the transformation, whereas β-H-containing alkylzinc reagents lead to a mixture of cross-coupling and hydrogenation products.

The design and utilization of dual sites for synergistic catalysts has been recognised as an efficient method towards high-efficiency catalysis in the cyanosilylation of aldehydes, which gives key intermediates for the synthesis of a number of valuable natural and pharmaceutical compounds. However, most of the reported dual-site catalysts for this reaction were homogeneous, accompanied by potential deactivation through internal complexation of the dual sites. Herein, by the rational selection of an uncoordinated tertiary nitrogen based tricarboxylic ligand (tris[(4-carboxyl)-phenylduryl]amine, H3TCBPA), a new three-dimensional calcium-based metal-organic framework (MOF), Ca3(TCBPA)2(DMA)2(H2O)2 (1, where TCBPA = ionized tris[(4-carboxyl)-phenylduryl]amine and DMA = N,N-dimethylacetamide), possessing accessible dual catalytic sites, Lewis-basic N and Lewis-acidic Ca, has been designed and constructed by a one-pot solvothermal reaction. As expected, 1 is capable of dually and heterogeneously catalysing the cyanosilylation of aldehydes at room temperature, and can be reused for at least 6 runs with a maximum turnover number (TON) of 1301, which is superior to most reported cases. Additionally, 1 shows CO2 adsorption ability and conversion with epoxides, which is beneficial for the establishment of a sustainable society.

To overcome the undesirable immune response and adverse side effects, and improve the therapeutic effect, developing a nanocarrier with good biocompatibility and high biosecurity to achieve highly efficient loading of drugs is still urgently needed. For the carriers of photodynamic therapy (PDT) photosensitizers, one of the special requirements is that the photosensitizers are better loaded on the carrier surface. In this paper, we give a paradigm of applying a pure DNA assembly as a biocompatible nanocarrier for highly efficient photosensitizer loading. Via simple DNA hybridization reactions, a pure DNA assembly (termed as a DNA nanolantern) with abundant modifiable sites was prepared and developed as a good nanocarrier for the loading of a porphyrin/G-quadruplex composite photosensitizer on the surface. The as-prepared DNA-based nanocomposite photosensitizer (DNA-NCPS) was characterized by various techniques and demonstrated to hold the charming features of nanoscale size, good monodispersity, robust biostability, strong light absorption in the biological transparent window, high tumor accumulation and cell internalization efficiency, excellent biological safety, low dark toxicity and high phototoxicity, thus showing great promise for PDT applications. Its PDT potential was verified by both in vitro cell and in vivo animal experiments. This study exhibits the great potential of pure DNA nanoassemblies in drug-loading, demonstrating their promising applications in therapy, diagnosis and theranostics.

The precise control over high-order DNA architecture assembly might be challenging due to complicated circuit design and functional unit synthesis. Here, we show an enzyme-free, catalytic assembly to construct nanometer and micrometer architectures in a bottom-up manner and applied them in nanoparticles and cell assembly.

The capture of highly radiotoxic 90Sr from an acidic waste solution during used fuel reprocessing and environmental remediation in a nuclear accident is desirable and challenging. Herein, we show a metal organic framework material (SNU-200) functionalized with an 18-crown-6-ether, whose specific binding site with an excellent affinity toward strontium leads to excellent Sr2+ adsorption capability under acidic conditions. This material exhibits a high adsorption capacity (44.37 mg g−1 at pH = 3), remarkable affinity (Kd = 3.63 × 104 mL g−1) and ultrahigh selectivity in the presence of interfering coexisting ions such as Na+, K+, Cs+, Mg2+, and Ca2+.

An organic molecular-ionic crystal of (TPPO–H)2SO4 exhibits moderate NLO response which is twice that of KDP and competing hydrogen-bonding interactions triggered high-Tc phase transition.

Nickel-catalyzed cross-electrophile coupling of aryl chlorides with allylic alcohols proceeds readily under mild conditions in the presence of zinc powder and MgCl2 to produce allylarenes in 25-92% yields. The reaction shows high regioselectivity and E/Z-selectivity, giving linear allylation products with an E configurated double bond when 1- or 3-arylallyl alcohols were used as the substrates. Functional groups including F, CF3, COOEt, NMe2, OMe, SiMe3, OH and vinyl groups as well as nitrogen-containing heterocycles were tolerated.

p-Nitrophenol and its derivatives can cause serious harm to the health of mankind and the earth's ecosystem. Therefore, it is necessary to develop a novel and rapid detection technology for p-nitrophenol and its derivative. Herein, excellent water-soluble, large-size and dual-emissive neuron cell-analogous carbon-based probes (NCNPs) have been prepared via a solvothermal approach, using o-phenylenediamine as the only precursor, which exhibit two distinctive fluorescence (FL) peaks at 420 and 555 nm under 345 nm excitation. The NCNPs show a neuron cell-like branched structure, are cross-connected, and are in the range of 10-20 nm in skeleton diameter. Interestingly, their blue-green dual-colour fluorescence is quenched by p-nitrophenol or its derivative due to the specific mechanism of the ππ stacking interactions or internal filtration effect. Accordingly, a simple, rapid, direct and free-label ratiometric FL detection of p-nitrophenol is proposed. An excellent linear relationship shows linear regions over the range of 0.1-50 μM between the ratio of the FL intensity (FL555 nm/FL420 nm) and the concentrations of p-nitrophenol. The detection limit is as low as 43 nM (3σ). Importantly, the NCNP-based probe also shows acceptable repeatability and reproducibility for the detection of p-nitrophenol and its derivatives, and the recovery results for p-nitrophenol in real wastewater samples are favourable.

The synthesis of hydrogen peroxide (H2O2) via two-electron (2e−) oxygen reduction reaction (ORR) electrocatalysis has garnered extensive attention as an appealing green and safe production technology. However, the key progress is still strongly dependent on developing highly active, selective and stable electrocatalysts. Here, guided by first-principles calculations, we developed a rational design for nitrogen (N) and oxygen (O) tailoring of carbon materials by precisely controlling the pyridinic N (Pydn-N) structure and the oxygen doping. The second nearest C atoms of Pydn-N were identified to be the active site, and this is suppressed owing to its local chemical environment and increase in the oxygen dopant content. Experimentally, high-temperature hydrogenation (HTH) regulates the Pydn-N content and synchronous oxygen removal for N,O co-doped carbons (CNO-x). The increment of Pydn-N from 37.42% up to 39.73%, along with oxygen removal from 5.24 at% down to 3.80 at% after HTH, promotes the H2O2 selectivity and electron transfer number (n) to 82% and 2.36. The H2O2 production rate is stable at around 200 mmol gcat−1 h−1 and a faradaic efficiency (F.E.) of up to 80% was recorded during the initial 4 h. The long-term H2O2 production further highlights the significance of sustaining the Pydn-N structure, modulating the solid carbon active site.

Accurate and specific analysis of adenosine triphosphate (ATP) expression levels in living cells can provide valuable information for understanding cell metabolism, physiological activities and pathologic mechanisms. Herein, DNA nanolantern-based split aptamer nanoprobes are prepared and demonstrated to work well for in situ analysis of ATP expression in living cells. The nanoprobes, which carry multiple split aptamer units on the surface, are easily and inexpensively prepared by a “one-pot” assembly reaction of four short oligonucleotide strands. A series of characterization experiments verify that the nanoprobes have good monodispersity, strong biostability, high cell internalization efficiency, and fluorescence resonance energy transfer (FRET)-based ratiometric response to ATP in the concentration range covering the entire intracellular ATP expression level. By changing the intracellular ATP level via different treatments, the nanoprobes are demonstrated to show excellent performance in intracellular ATP expression analysis, giving a highly ATP concentration-dependent ratiometric fluorescence signal output. ATP-induced formation of large-sized DNA aggregates not only amplifies the FRET signal output, but also makes in situ ATP-imaging analysis in living cells possible. In situ responsive crosslinking of nanoprobes also makes them capable of lighting up the mitochondria of living cells. By simply changing the split aptamer sequence, the proposed DNA nanolantern-based split aptamer strategy might be easily extended to other targets.

Functionalized elastomer hydrogels with tough and stretchable mechanics are desired soft materials extensively investigated for various field applications from soft electronics to sensors. Herein, we rationally designed a luminescent elastomer hydrogel by combining the functional carbon nitride (CN) unit cross-linkers with hydrophilic polymer chains into three-dimensional (3D) networks. The aqueous exfoliated and dispersed CN initiated the photopolymerization and gelation of an acrylamide (AM) monomer into a polyacrylamide (PAM)-CN elastomer hydrogel (PAM-CN ESH) under Xe light irradiation, without any conventional initiators and cross-linkers. Moreover, the mechanical attributes of toughness, stretchability and shape recovery for the PAM-CN ESH can be modulated by swelling in ethanol and water to form uniform and dense interlinked channels. Besides, the optical transparent PAM-CN ESH presents enhanced stable blue fluorescence emission around 430 nm, and accurately recognizes and detects Al3+ in an aqueous solution with a limit of detection (LOD) of 0.26 μM.

In recent years, DNA has been widely noted as a kind of material that can be used to construct building blocks for biosensing, in vivo imaging, drug development, and disease therapy because of its advantages of good biocompatibility and programmable properties. However, traditional DNA-based sensing processes are mostly achieved by random diffusion of free DNA probes, which were restricted by limited dynamics and relatively low efficiency. Moreover, in the application of biosystems, single-stranded DNA probes face challenges such as being difficult to internalize into cells and being easily decomposed in the cellular microenvironment. To overcome the above limitations, DNA nanostructure-based probes have attracted intense attention. This kind of probe showed a series of advantages compared to the conventional ones, including increased biostability, enhanced cell internalization efficiency, accelerated reaction rate, and amplified signal output, and thus improved in vitro and in vivo applications. Therefore, reviewing and summarizing the important roles of DNA nanostructures in improving biosensor design is very necessary for the development of DNA nanotechnology and its applications in biology and pharmacology. In this perspective, DNA nanostructure-based probes are reviewed and summarized from several aspects: probe classification according to the dimensions of DNA nanostructures (one, two, and three-dimensional nanostructures), the common connection modes between nucleic acid probes and DNA nanostructures, and the most important advantages of DNA self-assembled nanostructures in the applications of biosensing, imaging analysis, cell assembly, cell capture, and theranostics. Finally, the challenges and prospects for the future development of DNA nanostructure-based nucleic acid probes are also discussed., In recent years, DNA has been widely noted as a kind of material that can be used to construct building blocks for biosensing, in vivo imaging, drug development, and disease therapy because of its advantages of good biocompatibility and programmable properties.

Errors in elucidating the structures of four natural classes of prenylated aromatic compounds with 2,3-epoxy, 2,3-dihydroxy, and cyclization with an ortho-phenolic hydroxyl to give a pyran or furan ring moiety are frequent and inevitable. Based on rigorous literature research and a series of chemical transformation experiments, a rule for the rapid determination of these four classes of prenylated derivates based on 13C NMR data was formulated, and 57 corrections featuring these fragments were accordingly reported.

Background Ascorbic acid (AA), dopamine (DA), uric acid (UA), and nitrite (NO2−) are essential biomarkers for human metabolism and can be used to indicate some chronic diseases and metabolic disorders, including scurvy, Parkinson’s disease, hyperuricemia, and kidney disease. Objective A multifunctional electrochemical sensor that can integrate the detection of these species was constructed using nanoporous gold (NPG) as a recognition element to modify glassy carbon electrode (GCE). Methods The electrochemical performance of the multifunctional electrochemical sensor was investigated toward AA, DA, UA, and NO2− in citrate buffer solution (CBS, 100 mM, pH 4.0) and human serum using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Results In the quaternary mixture detection, the resulting NPG/GCE electrode displayed four independent oxidation peaks with wide peak separations. Further, the NPG/GCE electrode showed good linear responses with the sensitivities of 32, 1103, 71, and 147 μA/mM/cm2 and the detection limits of 1.58, 0.17, 0.37, and 0.36 μM for AA, DA UA, and NO2−, respectively. Additionally, the NPG/GCE electrode exhibited great anti-interference and was successfully applied in human serum samples. Conclusions These results indicate that the NPG/GCE electrode can simultaneously and selectively detect AA, DA, UA, and NO2−, which has the potential for application and diagnosis in the screening and diagnosis of chronic diseases and metabolic disorders. Highlights A multianalyte electrochemical sensor was fabricated for human metabolites detection. The sensor displayed good performance in the simultaneous detection of AA, DA, UA, and NO2− and applied to human serum samples.