Flexible molecularly imprinted fiber library for the metabolic analysis of bisphenol F and ecological risk evaluation.

Bisphenol F (BPF) has evoked global attentions due to its ubiquity and detrimental effects. Herein, a flexible molecularly imprinted fiber library was firstly proposed for the metabolic analysis of BPF in aquatic ecosystems. The library includes flexible single fibers and fiber arrays to precisely identify BPF and its metabolites with a wide range of polarities.

Nontargeted screening of aldehydes and ketones by chemical isotope labeling combined with ultra-high performance liquid chromatography-high resolution mass spectrometry followed by hybrid filtering of features.

Aldehydes and ketones are important carbonyl compounds that are widely present in foodstuffs, biological organisms and human living environment. However, it is still challenging to comprehensively detect and capture them using liquid chromatography - mass spectrometry. In this work, a chemical isotope labeling (CIL) coupled with ultra-high performance liquid chromatography - high resolution mass spectrometry (UHPLC-HRMS) strategy was developed for the capture and detection of this class of compounds.

Natural circulation of tick-borne severe fever with thrombocytopenia syndrome virus in the city ecosystem, China.

• Hedgehogs and ticks can maintain the natural circulation of SFTSV in the city ecosystem. • Hedgehogs and ticks are becoming common in Beijing. • Parthenogenetic ticks are discovered in Beijing.

A molecularly imprinted fiber array solid-phase microextraction strategy for simultaneous detection of multiple estrogens.

A kind of selective enrichment material based on a homemade molecularly imprinted polymer (MIP) fiber array with high adsorption capacity was developed for the accurate analysis of estrogens in food samples. Here, the MIP with 17β-estradiol as the template was obtained by polymerization. The chemical composition, morphologies, surface area, and pore size of the polymer were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer-Emmett-Teller theory.

Botanical discrimination and classification of Mentha plants applying two-chiral column tandem GC-MS analysis of eight menthol enantiomers.

The concentration and distribution of menthol enantiomers have great significance in discriminating natural mint varieties and evaluating the origin of foodstuffs containing menthol additives. However, the chiral separation of eight chiral menthol enantiomers in Mentha plants offers an easy approach to eliminating or reducing the identification technology problem. The application of derivatized β-cyclodextrin capillary chiral column coupled with derivatized γ-cyclodextrin capillary chiral column, and gas chromatography-mass spectrometry (GC-MS) technology, to isolate and analyze eight chiral menthol enantiomers in 23 natural Mentha plants was investigated.

Hedgehogs as Amplifying Hosts of Severe Fever with Thrombocytopenia Syndrome Virus, China.

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tickborne bandavirus mainly transmitted by Haemaphysalis longicornis ticks in East Asia, mostly in rural areas. As of April 2022, the amplifying host involved in the natural transmission of SFTSV remained unidentified. Our epidemiologic field survey conducted in endemic areas in China showed that hedgehogs were widely distributed, had heavy tick infestations, and had high SFTSV seroprevalence and RNA prevalence.

Direct adsorption sampling and ambient mass spectrometry analysis of tobacco smoke with porous paper strips.

Chemical analysis of atmospheric aerosols by conventional analytical methods is usually required to perform complicated and time-consuming sample preparation processes. In recent decades, ambient ionization mass spectrometry (AI-MS) methods have been proven to be simple, rapid, and effective analytical tools for direct analysis of various complex samples. In this work, we applied porous paper filters for direct adsorptive sampling of tobacco smoke, and then the sampled paper filters were performed the emitters of the paper spray ionization (PSI) device.

Determination and Difference Analysis of Phenolic Compounds in Smokers' Saliva and Mainstream Smoke.

To study the differences in phenolic compounds between tobacco smokers' saliva and mainstream smoke, a method was developed for the analysis of 12 phenolic compounds in saliva and mainstream smoke based on ultrahigh-performance liquid chromatography with fluorescence detection (UPLC-FLD). The contents and distributions of phenolic compounds in tobacco smokers' saliva and mainstream smoke were compared. The results were as follows: (1) Phenolic compounds were quantitatively analyzed by the internal standard method using 4-fluorophenol as an internal standard.

FeO@SiO@VAN Nanoadsorbent Followed by GC-MS for the Determination of Polycyclic Aromatic Hydrocarbons at Ultra-Trace Levels in Environmental Water Samples.

In the present study, silica-coated magnetic nanoparticles functionalized with vancomycin (FeO@SiO@VAN) were synthesized. The FeO@SiO@VAN nanocomposite was used as a sorbent for the magnetic solid-phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) from environmental water, followed by GC-MS. The nanocomposite was characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and nitrogen sorption.

Generic imprinted fiber array strategy for high-throughput and ultrasensitive simultaneous determination of multiple neonicotinoids.

Herein, a new generic fiber array based on molecular imprinting solid-phase microextraction (MIP-SPME) technology, was described to enrich trace multiple neonicotinoids with high flux from the food matrix. To begin with adsorption experiments coupled with theoretical calculations provided universal means for selecting the preferred template molecule clothianidin (CLT). Results demonstrated that the CLT-MIP fiber array exhibited significantly superior enrichment ability of 1189-2356-folds for six neonicotinoids compared with two kinds of commercial fiber arrays.

Components and Persistent Free Radicals in the Volatiles during Pyrolysis of Lignocellulose Biomass.

Persistent free radicals (PFRs) may cause negative impacts to human health and the environment because of the induced reactive oxygen species. We expect that PFRs could be generated in the condensable volatiles formed during lignocellulose biomass pyrolysis. Elucidating the structural origin and the formation mechanism of PFRs is important for an in-depth understanding of air pollutants from the pyrolysis or combustion of lignocellulose biomass.

Chiral molecularly imprinted polymeric stir bar sorptive extraction for naproxen enantiomer detection in PPCPs.

Chiral micropollutant analysis in pharmaceuticals and personal care products (PPCPs) is interesting but challenging. We firstly developed a series of chiral molecularly imprinted polymeric (CMIP) stir bar sorptive extraction coatings by combining a chiral template with chiral functional monomers via a click reaction for naproxen enantiomer analysis in PPCPs. Heterochiral selectivity was observed in the molecule recognition of the CMIP coatings, which demonstrated good adsorption capability for the chiral template and its structurally similar chiral compounds.

Formation of persistent free radicals in biochar derived from rice straw based on a detailed analysis of pyrolysis kinetics.

The presence of persistent free radicals (PFR) in biochars may greatly broaden the application of biochars in pollution control, but may also cause negative impacts to the environment. Understanding the structural basis and the formation mechanisms of PFR is essential for a targeted biochar production and application. This study used rice straw (RS), a ubiquitous agricultural waste, to investigate the generation processes of PFR in relation to RS pyrolysis kinetics.

[Tandem technologies in chromatographic analysis].

The acquisition of chemical compounds information from samples depends on the separation as well as detection techniques. Usually, it is difficult to achieve the separation and identification of all components in complex samples by a simple one-dimensional chromatographic method. Thus, tandem technologies, which mainly include column tandem connection techniques, detector tandem connection techniques, and multidimensional chromatography, have aroused widespread interest.

Three new isoflavones from the (Willd.) and their bioactivities.

Three new isoflavones, 7-acetyl-4',6-dimethoxy-isoflavone (), 7-acetyl-4'-hydroxy-6-methoxy-isoflavone () and 7-acetyl-6,8-dimethoxy-4'-hydroxy-isoflavone (), together with five known flavones (-), were isolated from the (Willd.). Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques.

Two new benzolactones from the leaves of Nicotiana tabacum and their anti-tobacco mosaic virus activities.

Two new benzolactones, 5-methyl-6-prenyl-isobenzofuran-1(3H)-one (1), 5-hydroxymethyl-6-prenyl-isobenzofuran-1(3H)-one (2), together with four known phenolic compounds (3-6), were isolated from the leaves of Nicotiana tabacum. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1-6 were evaluated for their anti-tobacco mosaic virus (anti-TMV) activities.

Isolation of fucoxanthin from edible brown algae by microwave-assisted extraction coupled with high-speed countercurrent chromatography.

A rapid and efficient method for the separation and purification of fucoxanthin from edible brown algae by microwave-assisted extraction coupled with high-speed countercurrent chromatography was developed. The algae were first extracted using microwave-assisted extraction, then the dried extract was dissolved and directly introduced into the high-speed countercurrent chromatography system with a two-phase solvent system consisting of hexane-ethyl acetate-ethanol-water (5:5:6:4, v/v/v/v). The isolation was done in less than 75 min, and a total of 0.

Ultrasonic microwave-assisted extraction coupled with high-speed counter-current chromatography for the preparation of nigakinones from Picrasma quassioides (D.Don) Benn.

Introduction: Nigakinones are the main effective compounds of Picrasma quassioides (D. Don) Benn and are widely used in traditional Chinese medicine, therefore a rapid and efficient separation and purification method is necessary.

Objective: To develop a new method based on ultrasonic microwave-assisted extraction (UMAE) and high-speed counter-current chromatography (HSCCC) for the rapid separation and purification of nigakinone and methylnigakinone from P.

Unintended compositional changes in transgenic rice seeds ( Oryza sativa L.) studied by spectral and chromatographic analysis coupled with chemometrics methods.

Unintended compositional changes in transgenic rice seeds were studied by near-infrared reflectance, GC-MS, HPLC, and ICP-AES coupled with chemometrics strategies. Three kinds of transgenic rice with resistance to fungal diseases or insect pests were comparatively studied with the nontransgenic counterparts in terms of key nutrients such as protein, amino acids, fatty acids, vitamins, elements, and antinutrient phytic acid recommended by the Organization for Economic Co-operation and Development (OECD). The compositional profiles were discriminated by chemometrics methods, and the discriminatory compounds were protein, three amino acids, two fatty acids, two vitamins, and several elements.