Orientation Growth of N-Doped and Iron-Based Metal-Organic Framework and Its Application for Removal of Cr(VI) in Wastewater.

A series of NH2-functionalized nano-sized magnetic metal-organic frameworks (MOFs) were prepared in this study for Cr(VI) removal from wastewater. It was observed that not only the morphological, i.e., orientation growth of N-doped and iron-based metal-organic frameworks, but also the adsorption of magnetic MOFs is largely related to the used amount of ammonium hydroxide in preparation. For example, with increasing amounts of ammonium hydroxide used in preparation, the morphology of magnetic MOFs changed from spherical to cube and triangular cone. Moreover, the maximum adsorption capacity of spherical-magnetic MOFs, cubic-magnetic MOFs and triangular cone-magnetic MOFs could be up to 204.08 mg/g, 232.56 mg/g and 270.27 mg/g, respectively. Under optimal conditions, the adsorption process of magnetic MOFs for Cr(VI) was consistent with the pseudo-second-order rate equation (R2 = 1) and Langmuir isotherm model (R2 > 0.99). Therefore, magnetic MOFs developed in this work offered a viable option for the removal of Cr(VI) from wastewater.

Amphiphilic Polymer Capped Perovskite Compositing with Nano Zr-MOF for Nanozyme-Involved Biomimetic Cascade Catalysis.

CsPbX3 perovskite nanocrystal (NC) is considered as an excellent optical material and is widely applied in optoelectronics. However, its poor water stability impedes its study in enzyme-like activity, and further inhibits its application in biomimetic cascade catalysis. Herein, for the first time, the oxidase-like and ascorbate oxidase-like activities of an amphiphilic polymer capped CsPbX3 are demonstrated, and its catalytic mechanism is further explored. Furthermore, an all-nanozyme cascade system (multifunctional CsPbBr3 @Zr-metal organic framework (Zr-MOF) and Prussian blue as oxidase-like and peroxidase-like nanozyme) is constructed with a portable paper-based device for realizing the dual-mode (ratiometric fluorescence and colorimetric) detection of ascorbic acid in a point-of-care (POC) fashion. This is the first report on the utilization of all-inorganic CsPbX3 perovskite NC in biomimetic cascade catalysis, which opens a new avenue for POC clinical disease diagnosis.

A bimetallic metal-organic framework with high enzyme-mimicking activity for an integrated electrochemical immunoassay of carcinoembryonic antigen.

Metal-organic frameworks (MOFs) show excellent catalytic activity and have been widely applied in diagnosis of diseases and tumors. However, current assay methods usually involve cumbersome configurations and complicated procedures, which inhibit their practical applications. Hence, a Cu-Ni MOF/carbon printed electrode (CPE)-based integrated electrochemical immunosensor was constructed for highly sensitive and efficient determination of carcinoembryonic antigen (CEA). First, highly conductive carbon ink was screen-printed onto a polyethylene terephthalate substrate to manufacture a CPE. Afterward, an aminated Cu-Ni MOF was prepared by a typical solvothermal strategy and modified on the CPE. Owing to its excellent peroxidase activity, the Cu-Ni MOF can catalytically oxidize hydroquinone using hydrogen peroxide, which greatly amplifies the peak current signal. Then the formation of an immune complex inhibited the catalytic activity of the MOF, thus enabling the quantitative determination of CEA content with a wide linear range of 0.5 pg mL-1-500 ng mL-1 and a low detection limit of 0.16 pg mL-1. Furthermore, the Cu-Ni MOF/CPE-based integrated portable electrochemical immunosensor also showed satisfactory performance in the detection of CEA in clinical serum samples with excellent accuracy, showing great potential for application in point-of-care disease diagnosis.

Structural characterization and anti-osteoporosis effect of an arabinomannan from Anemarrhena asphodeloides Bge.

To discover the polysaccharide with anti-diabetic osteoporosis (DOP) activity and clarify its structure, an arabinomannan (PAAP-1B) with a molecular weight of 14.0 kDa was isolated from Anemarrhena asphodeloides Bge. using column chromatography. It consists of arabinose, mannose, and galactose in a molar ratio of 6:3:1. PAAP-1B has a backbone composed of 1,5-α-Araf, 1,4-ß-Manp, and 1,6-ß-Galp residues that are branched at C3 of α-Araf and ß-Galp residues. The side chains are T-α-Araf, T-α-Manp, T-ß-Galp, and 1,6-ß-Galp. PAAP-1B attenuated DOP and reduced ferroptosis in the femurs and tibias of alloxan-induced mice. It also suppressed ferroptosis in advanced glycation end product-induced osteoblasts by decreasing 4-hydroxynonenal, malondialdehyde, mitochondrial reactive oxidative species levels, and lipid peroxidation, while reversing the downregulation of solute carrier family 7 membrane 11 and glutathione expression.

Polyelectrolyte-grafted anion exchangers with hydrophilic intermediate layers for ion chromatography.

The hydrophobicity of polymer-based anion exchangers is a persistent problem in suppressed anionic chromatography (SAC) due to its adverse effect on chromatographic performance. Herein we describe polyelectrolyte-grafted anion exchangers with modified hydrophilic intermediate layers. The anion exchangers were functionalized by successively grafting a linear cationic condensation polymer (LCCP), a preprepared polyelectrolyte. The carboxylic/hydroxylic intermediate layers formed during thiol-radical-mediated polymerization exert distinct effects on the phase capacity and hydrophobicity. The separation of typical inorganic anions, polarizable anions, and organic acids shows that the anion exchangers display good performance in SAC mode.

Nanomaterials with Excellent Adsorption Characteristics for Sample Pretreatment: A Review.

Sample pretreatment in analytical chemistry is critical, and the selection of materials for sample pretreatment is a key factor for high enrichment ability, good practicality, and satisfactory recoveries. In this review, the recent progress of the sample pretreatment methods based on various nanomaterials (i.e., carbon nanomaterials, porous nanomaterials, and magnetic nanomaterials) with excellent adsorption efficiency, selectivity, and reproducibility, as well as their applications, are presented. Due to the unique nanoscale physical-chemical properties, magnetic nanomaterials have been used for the extraction of target analytes by easy-to-handle magnetic separation under a magnetic field, which can avoid cumbersome centrifugation and filtration steps. This review also highlights the preparation process and reaction mechanism of nanomaterials used in the sample pretreatment methods, which have been applied for the extraction organophosphorus pesticides, fluoroquinolone antibiotics, phenoxy carboxylic acids, tetracycline antibiotics, hazardous metal ions, and rosmarinic acid. In addition, the remaining challenges and future directions for nanomaterials used as sorbents in the sample pretreatment are discussed.

Safety of a Sustainably Produced, Bioengineered, Nature-Identical Salidroside Compound.

Bioactive phytochemicals such as salidroside have been studied to understand the beneficial effects of Rhodiola rosea, an herbaceous plant used in traditional medicine to increase energy and treat a variety of health issues. However, Rhodiola plants are often slow-growing, and many are endangered in their native habitats. Thus, there is a need for safe, alternative supplies of key phytochemicals from Rhodiola. The salidroside subject of this safety study is a synthetic biology product from fermentation of a bioengineered E. coli that produces salidroside. Here, we present comprehensive test results that support the safety of salidroside manufactured via a patented sustainable bioengineering manufacturing process. In vitro bacterial reverse mutation assays with the bioengineered salidroside show no mutagenicity in any of the concentrations tested. In vivo toxicity studies in rats show no adverse effects from the salidroside product. Based on the results of these studies, we conclude that the bioengineered salidroside discussed here is not genotoxic and demonstrates a no-observed-adverse-effect level (NOAEL) at least 2000 mg/kg bw/day in male and female Sprague-Dawley rats. This study supports that the salidroside compound produced using bioengineered E. coli is a viable alternative to salidroside produced from harvested Rhodiola plants for use as a dietary supplement, food ingredient, or potentially as a pharmaceutical product.

hECA: The cell-centric assembly of a cell atlas.

The accumulation of massive single-cell omics data provides growing resources for building biomolecular atlases of all cells of human organs or the whole body. The true assembly of a cell atlas should be cell-centric rather than file-centric. We developed a unified informatics framework for seamless cell-centric data assembly and built the human Ensemble Cell Atlas (hECA) from scattered data. hECA v1.0 assembled 1,093,299 labeled human cells from 116 published datasets, covering 38 organs and 11 systems. We invented three new methods of atlas applications based on the cell-centric assembly: "in data" cell sorting for targeted data retrieval with customizable logic expressions, "quantitative portraiture" for multi-view representations of biological entities, and customizable reference creation for generating references for automatic annotations. Case studies on agile construction of user-defined sub-atlases and "in data" investigation of CAR-T off-targets in multiple organs showed the great potential enabled by the cell-centric ensemble atlas.

Magnetic nanomaterials with unique nanozymes-like characteristics for colorimetric sensors: A review.

Colorimetric sensors for the rapid detection of numerous analytes have been widely applied in many fields such as biomedicine, food industry and environmental science due to their highly sensitive and selective response, easy operation and visual identification by naked eyes. In this review, the recent progress of the colorimetric sensors based on the magnetic nanomaterials with unique nanozymes-like catalytic activity (magnetic nanozyme) and their colorimetric sensing applications are presented. Emerging magnetic nanozyme-based colorimetric sensors, such as metal oxide/sulfides-based, metal-based, carbon-based, and aptamer-conjugated magnetic nanomaterials, offer many desirable features for target analytes detection. And due to the unique nanoscale physical-chemical properties, magnetic nanozymes have been used to mimic the catalytic activity of natural enzymes such as peroxidases, oxidases and catalases. This review also highlights the catalytic mechanisms of enzyme-like reactions, and promising colorimetric sensing system for the detection of chemical compounds like H2O2, pesticide, ascorbic acid, dopamine, tetracyclines, perfluorooctane sulfonate, phenolic compounds, heavy metal ion and sulfite have been deeply discussed. In addition, the remaining challenges and future directions in utilizing magnetic nanozyme for colorimetric sensors are addressed.

Determination of Organophosphorus Esters in Fall Protection Equipment by Accelerated Solvent Extraction and Solid-Phase Extraction Coupled with LC-MS/MS Detection.

An analysis method was established to determine 14 organophosphorus ester (OPE) flame retardants in fall protection equipment by combining accelerated solvent extraction (ASE) and solid-phase extraction (SPE) with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The ASE parameters were optimized as follows: static extraction with acetonitrile at 80°C for 5 min for two cycles. The combined extract was purified with the ENVI-18 cartridge before further analysis. A HILIC column was used to separate the OPEs using an acetonitrile/water mixture as the mobile phase with the detection by the electrospray ionization mass spectrometry, which was operated under the positive mode. Under optimized conditions, the limit of detection for the target OPEs ranged in 0.015-1.33 ng/g, with a spike recovery of 71.6%-114% and a relative standard deviation of 0.8%-11.2%. The developed method was used to analyze OPEs in fall protection equipment (safety helmets and ropes), where OPEs were all detectable. Safety ropes displayed a higher concentration of OPEs than ones in safety helmets, with the pollutants being mainly triphenyl phosphate, 2-ethylhexyl diphenyl phosphate (EHDPP), tri(2-ethylhexyl) phosphate, and tri-n-butyl phosphate in the range of 11.07 ng/g‒815.53 ng/g. The EHDPP was the dominant compound in safety helmets with the concentration from 26.84 to 95.29 ng/g, while the other OPEs in safety helmets were lower than 5.136 ng/g. The potential health and environmental risks of these fall protection equipment during their use and disposal call for further attention.

Determination of Trace Bromate in Drinking Water with High Chloride Matrix by Cyclic Ion Chromatography.

An ion chromatography (IC) system with switching recycling column was developed for the determination of bromate in drinking water with high chloride content. The system included a pump, two switching valves, guard column and analytical column, suppressor and a conductivity detector. In this method, the single eluent was used for both online collection and matrix elimination, and bromate was eluted from the concentrator column to the analytical column circularly. Under the optimized separation conditions, the method showed good linearity (r = 0.9995) in the range of 1-100 µg/L and repeatability (RSD ≤ 4.80%, n = 6). The limit of detection was 0.2 µg/L (S/N = 3) with 1000 µL sample volume injections. The method was applied to analysis of drinking and tap waters, and satisfactory recoveries of spiked samples between 96.8% and 108.7% were obtained. The result showed that the recycling column-switching system can be useful for the determination of traces of bromate in high-chloride samples, which is required in production of the drinking water and quality control of the final product.

Preparation of sheet-like covalent organic frameworks and their application for efficient preconcentration of 4-(tert-octyl)-phenol and 4-nonylphenol in textiles.

In the design of highly ordered (covalent organic frameworks) COFs with "ordered domains size and orientation" construction in a well-defined arrangement, the molecular monomers are the key factors. Here, the effect of molecular monomers on the construction of COFs has been studied, and two kinds of molecular monomers, i.e., ethanediamine (flexible amine ligand) and 4,4'-diaminobiphenyl (rigid amine ligand) have been used for developing sheet-like COFs-I and sheet-like COFs-II, respectively. Furthermore, they have been evaluated in the dispersive solid phase extraction (dSPE) procedure for textiles prior to the analysis of alkylphenol by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). The results showed that, the optimal usage amount of sheet-like COFs-II used in the dSPE procedure was less than that of sheet-like COFs-I, which may be explained by much higher adsorption capacity of sheet-like COFs via hydrogen-bonding and π-π stacking interactions. Rectilinear calibration graphs were obtained for 4-(tert-octyl)-phenol (4-tOP) and 4-nonylphenol (4-NP) in the range 0.2-20 µg/kg with determination coefficient (r2) higher than 0.9990, and the limits of detection (LODs) of 4-tOP and 4-NP were 0.039 µg/kg and 0.048 µg/kg, respectively. The developed method has been successfully applied to analysis of 50 textile samples, in which 4-tOP and 4-NP were found in six samples with concentrations in the range of 1.6 µg/kg-20.9 µg/kg.

Ultrasound-assisted synthesis of clover-shaped nano-titania functionalized covalent organic frameworks for the dispersive solid phase extraction of N-nitrosamines in drinking water.

In this study, three batches of nano-titania functionalized covalent organic frameworks were acquired depending on different solvothermal reaction stages (24 h, 48 h and 72 h), which were named as single roll-up shaped nano-titania functionalized COFs (SSTF-COFs), double roll-up shaped nano-titania functionalized COFs (DSTF-COFs) and clover-shaped nano-titania functionalized covalent organic framework (CSTF-COFs), respectively. After comparing their extraction performances, the more efficient and stable CSTF-COFs were selected as sorbent for the dispersive solid phase extraction (dSPE) of eight target N-nitrosamines in drinking water, followed by the determination with liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). Owing to the introduction of hydroxy groups, CSTF-COFs showed high extraction efficiency for N-nitrosamines with a wide range of polarities through hydrogen bonding interaction, hydrophobic interaction and hydrophilic interaction. Under optimum conditions, the developed method provided relatively low limits of detection (0.13-2.45 ng/L) and satisfactory recoveries (88.6-105.5%), with relative standard deviations (RSDs) less than 8.3%. Therefore, with the assistance of CSTF-COFs, trace levels of N-nitrosamines were quantitatively and sensitively determined in 31 out of 460 bottled drinking water samples in a sensitive and convenient way.

Determination of inorganic anions in weak acids by using ion exclusion chromatography - Capillary ion chromatography switching column technique.

An improved "heart-cut" column-switching method combining ion-exclusion column, monolithic anion exchange concentrator and capillary anion-exchange column is developed and successfully applied for the determination of inorganic anions (Cl-, Br-, NO3- and HPO42-) at trace level in weak acids. The quantitative determination of selected inorganic anions in the samples of fifteen weak acids and hydrogen peroxide are accomplished with analysis time of 45 min per sample. The obtained limits of detection (LODs) are in the range of 2.1-32.6 ng/L based on the s/n = 3 and injection volume of 50 µL. RSDs for retention time and peak area were all ≤1.89%. A spike-recovery study was performed under these conditions and satisfactory recoveries between 85.3 and 103.9% for all studied anions were obtained.

The bioaccessibility of iodine in the biofortified vegetables throughout cooking and simulated digestion.

Biofortification of crops with exogenous iodine is a novel strategy to control iodine deficiency disorders (IDD). The bioaccessibility of iodine (BI) in the biofortified vegetables in the course of soaking, cooking and digestion, were examined. Under hydroponics, the concentration of iodine in leafstalks of the celery and pakchoi increased with increasing exogenous iodine concentration, 54.8-63.9% of the iodine absorbed by pakchoi was stored in the soluble cellular substance. Being soaked in water within 8 h, the iodine loss rate of the biofortified celery was 3.5-10.4% only. More than 80% of the iodine in the biofortified celery was retained after cooking under high temperature. The highest BI of the biofortified vegetables after digestion in simulated gastric and intestinal juice amounted to 74.08 and 68.28%, respectively. Factors influencing BI included pH, digestion duration, and liquid-to-solid ratio. The high BI of the biofortified vegetables provided a sound reference for the promotion of iodine biofortification as a tool to eliminate the IDD.

Simultaneous Determination and Investigation of Nine Fungicides in Fruits Using Diethylenetriamine-Functional Magnetic Core-Shell Polymer Modified Graphene Oxide as an Efficient Adsorbent Coupled to UPLC-HRMS.

In this study, diethylenetriamine-functional magnetic core-shell polymer modified graphene oxide (DETA-MPs-GO) was prepared via precipitation polymerization and amidation reaction, and it was characterized by transmission electron microscopy (TEM), Fourier-transformed infrared spectroscopy (FTIR), and X-ray diffractometer (XRD). Subsequently, a magnetic solid-phase extraction (MSPE) procedure was applied to the as-synthesized DETA-MPs-GO for the detection of nine fungicides in fruit samples, prior to ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The homogenized fruit samples, spiked with D-labelled internal standards, were firstly extracted by 5 mL of acetonitrile twice and then purified by DETA-MPs-GO adsorbents. The optimization of the adsorption and elution conditions of DETA-MPs-GO toward fungicides was carried out to attain a satisfactory adsorption performance and desorption efficiency. The adsorption mechanism was carefully investigated, and the results revealed that a synergistic adsorption mechanism, including hydrogen bond and a π-π stacking interaction, was confirmed. Moreover, the limits of quantitation (LOQs) of the proposed approach were in the range of 0.01 to 0.30 µg/kg under the optimum conditions. The average recoveries at three spiking levels were 84.9% to 105.2%, with relative standard deviations (RSDs) varying from 0.8% to 8.2% (n = 6). The developed method was successfully utilized for the screening and detection of fungicides in 81 fruit samples purchased from markets. A detailed survey was carried out about the concentration distribution, types of fungicides, and combined use of fungicides in different fruits.

Co-evolution of Hormone Metabolism and Signaling Networks Expands Plant Adaptive Plasticity.

Classically, hormones elicit specific cellular responses by activating dedicated receptors. Nevertheless, the biosynthesis and turnover of many of these hormone molecules also produce chemically related metabolites. These molecules may also possess hormonal activities; therefore, one or more may contribute to the adaptive plasticity of signaling outcomes in host organisms. Here, we show that a catabolite of the plant hormone abscisic acid (ABA), namely phaseic acid (PA), likely emerged in seed plants as a signaling molecule that fine-tunes plant physiology, environmental adaptation, and development. This trait was facilitated by both the emergence-selection of a PA reductase that modulates PA concentrations and by the functional diversification of the ABA receptor family to perceive and respond to PA. Our results suggest that PA serves as a hormone in seed plants through activation of a subset of ABA receptors. This study demonstrates that the co-evolution of hormone metabolism and signaling networks can expand organismal resilience.

An innovative approach for iodine supplementation using iodine-rich phytogenic food.

Iodine, as one of the essential trace elements for human body, is very important for the proper function of thyroid gland. In some regions, people are still suffering from iodine deficiency disorder (IDD). How to provide an effective and cost-efficient iodine supplementation has been a public health issue for many countries. In this review, a novel iodine supplementation approach is introduced. Different from traditional iodine salt supplement, this approach innovatively uses cultivated iodine-rich phytogenic food as the supplement. These foods are cultivated using alga-based organic iodine fertilizer. The feasibility, mechanics of iodine absorption of plants from soil and the bioavailability of iodine-rich phytogenic food are further discussed.

[Determination of trace chloride in sodium sulfate of analytical reagent-grade by valve-switching ion chromatography].

A valve-switching ion chromatography system was developed for the determination of trace chloride in sodium sulfate using a single pump, a suppressor, two valves and three columns. Using this technique, the trace chloride was eluted from the concentrator column (IonPac TAC-ULP1, 23 mm x 5 mm) to the analytical column (IonPac AS18, 250 mm x 4 mm), and the sulfate flowed to the waste. Under the optimized separation conditions, the method showed good linearity (r2 > 0.999) in the range of 0.03 - 1 mg/L and the average recoveries of chloride were 98.0% - 103.0% with the relative standard deviation less than 2%. The limit of detection was 0.01 mg/L (S/N = 3). The results demonstrated that this system has the advantages of high sensitivity, facile automation and simple sample pretreatment, which might be a promising approach for the determination of trace chloride in high-purity reagents.

Determination of low-level anions in seawater by ion chromatography with cycling-column-switching.

An ion chromatographic cycling-column-switching system was developed for the determination of low-level anions (fluoride, nitrite, nitrate, bromide, sulfate, and phosphate) in seawater using a single pump, a suppressor, two valves, and three columns. Using this technique, the low-level anions were eluted from the concentrator column to the analytical columns circularly, and the matrix flowed to the waste. Under the optimized separation conditions, the method showed good linearity in the range of 0.05-25.0 mg/L and satisfactory repeatability (RSD<4%, n=6). The limits of detection were in the range of 2-23 µg/L (S/N=3). The result showed that the cycling-column-switching system was convenient and practical for the determination of trace anions in high-salinity samples.