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QuEChERS combined with ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was developed to analyze multi-class mycotoxins including aflatoxins, ochratoxins, and Alternaria toxins in apples and tomatoes. Using apples and tomatoes as the research models, the method performance had been evaluated, showing great convenience, high sensitivity, and good reliability. The limit of detections was of 0.05–20 μg/L. The average recovery values were from 71.3 to 119.4%. With respect to precision, the repeatability was lower than 14.4%. With the optimum method, risk monitoring of mycotoxins in fresh and stored apples and tomatoes was executed, which indicated the risk of contamination of Alternaria toxins in apples which were preserved over a period of time.

Polyhedral oligomeric silsesquioxanes (POSSs) are a class of important hybrid inorganic/organic materials. When POSSs are used as the building block in polymerization, the materials show superior performance over their organic counterparts in many areas due to the special Si–O cage structure. However, the stereoisomers (cis, trans) of polyhedral oligomeric silsesquioxane (POSS) show some differences in improving polymer property and it is difficult to get the pure stereoisomer by synthesis. Therefore, a method is required to separate and purify the mixture of POSSs. In this study, the isomers of POSS compounds and the impurities were separated by ultra-high performance supercritical fluid chromatography coupled quadrupole time-of-flight mass spectrometry (UHPSFC-QTof MS). To separate the isomers of POSS, the crucial parameters of UHPSFC-QTof MS were investigated. Under the optimal conditions, the isomers of product and impurities were separated in 4 min. On account of exact mass measurement, some impurities were identified. This is the first study on the analysis of isomers of POSS using UHPSFC-QTof MS. Based on this analysis method, it is helpful to optimize the conditions of synthesis.

Herein, a modified indirect method was established for the determination of 3-monochloropropane-1,2-diol esters (3-MCPDEs) and glycidyl esters (GEs), employing magnetic solid phase extraction by boronic acid-functionalized magnetic nanoparticles to replace the traditional clean-up procedure. Compared with routine methods, it has been proved to be more sensitive with limits of detection in the range of 0.02-1.5 μg/kg and less susceptible to contamination of phenylboronic acid derivatives and fatty acid methyl esters. The proposed method was applied to analyze 42 samples covering the entire infant formula (IF) production chain. Results revealed that homogenization process contributed 79-91 % of the total growth of the contaminants due to the vegetable oil addition, while the following evaporation and spray-drying processes contributed 9-21 % of the total growth owing to involved heat treatment. The GE levels in final IF products exceeded the maximum level set by EU regulation 2020/1322, indicating quality safety concerns in the production chain.

Lactoferrin (LF), a natural iron regulating glycoprotein, exists in animal milk and plays multiple beneficial roles. Bovine LF is obtained by separation and purification from cow's milk, and has been added as a food additive to functional foods and infant formula now. Therefore, accurate analysis of LF in these foods is very important, but there are challenges such as poor selective extraction and separation efficiency. In this work, considering the cis-diol in LF, boron-doped titania (B-doped TiO

Glycoprotein imprinted polymers have rapidly grown as excellent receptors for cancer targeting, diagnostics, inhibition, and nanomedicines as they specifically target glycans and glycosites overexpressed in various tumors. Compared to natural antibodies, they are easy to synthesize, stable, and cost-efficient. Currently, no study specifically discusses glycoproteins imprinting strategies for cancer theranostics. In this review, firstly we explored various factors involved in designing and synthesis of glycoprotein imprinted materials, including, the characteristics and choice of monomers for imprinting, types of templates and their interactions involved, and the imprinting methods. Secondly, the integration of these MIPs with different probes that have been applied for

The contamination of water is a high risk to human health, so there is an urgent need to rapidly detect water pollution in the field. Ion mobility spectrometry (IMS) is suitable for on-site analysis with the merit of rapid analysis and compact size. In this study, we developed a new method which coupled fabric phase sorptive extraction (FPSE) with IMS for rapid detection of polycyclic aromatic hydrocarbons (PAHs) in water present in the field. Polydimethylsiloxane (PDMS) was coated on the glass fiber cloth through a sol-gel reaction. After extracting the PAHs in water, the fabric coated PDMS could be directly put into the inlet of IMS instrument for thermal desorption. The PAHs were analyzed by the IMS instrument operated in the positive ion mode with a corona discharge (CD) ionization source. The primary parameters affecting extraction efficiency such as extraction time, extraction temperature, and ionic strength were investigated and optimized by using phenanthrene (Phe), benzo[a]anthracene (BaA) and benzo[a]pyrene (BaP) as model compounds. Under the optimal conditions, the FPSE-IMS detection limits were 5 ng ml−1,8 ng ml−1 and 10 ng ml−1 respectively. Satisfactory recoveries were obtained in the range from 80.5% to 100.5% by testing the spiked real water samples and validated by the standard method（HJ487-2009）. Based on the results, the method of FPSE-IMS could be feasibly applied for monitoring the water quality on-site and providing early warning in the field.

Many parts of the vehicle cabin generate volatile organic compounds (VOCs) and they are hazardous to humans. In this study, VOCs in the inner liner of automobile spare tire, and separately the significant materials used in it, like raw rubber and resins, were detected by gas chromatography-mass spectrometry (GC-MS) coupled with extracting method of static headspace sampling (SHS). By comparison, the sources of VOCs can be traced back to raw rubbers and resins. And the results indicated that alkylphenol resins are the most volatile raw materials, which would release 2,4,4-trimethyl-1-pentene, and 2,2,4,6,6-pentamethyl-3-heptene. Secondly, chlorobutyl rubber (CIIR) contained 3-methyl-pentane and methyl-cyclopentane. At the same time, through replacements of raw materials in initial formulation, such as alkylphenol resins and natural rubber (NR) with low VOCs, the total volatile organic compounds (TVOCs) discharged in inner liner could be reduced. We expected that the information gained from this work could provide references and positive significance for the manufacture of environmental-friendly tire products.

Furfural compounds are produced during infant formula production when heat treatment is involved. In this study, a robust method was established for determining potential and free furfural compounds (furfural, 5-methyl-2-furfural, 2-acetylfuran and 5-hydroxymethyl-2-furfural) using a modified QuEChERS technique coupled with GC-MS/MS. Further, 36 samples of two batches, covering the whole infant formula production chain were analyzed by the method to investigate how furfurals evolved during process. Then risk assessment was conducted using the Toxtree and T.E.S.T. software and evaluated by hazard quotient. Results showed the contents of bound and free 5-hydroxymethyl-2-furfural demonstrated largest increase during spray-drying (6-11 times) and homogenization stages (12-33 times), respectively. As the sum up of bound and free 5-hydroxymethyl-2-furfural, potential 5-hydroxymethyl-2-furfural was found can cause safety risks in the production chain due to the high hazard quotient value (3.11), indicating it should be controlled in homogenization and spray-drying stages.

Micro-tip-based solid-phase microextraction is considered as one of the green and powerful analytical sample preparation techniques, but its efficiency is severely hampered by some basic issues such as tedious fabrication, instability of sorbent bed, and blocking of the tip, especially for biological samples due to low permeability. These issues are tackled by introducing a flexible and hierarchical substrate in the microtip, having good mechanical strength and specific functionality to capture the desired biomolecules. Considering the well-ordered and flexible structure of melamine foam, it was used as a substrate and for hydrophilic interaction chromatography (HILIC). Metal-organic framework, due to its excellent characteristics, was grafted on its surface anchored by self-assembling polydopamine. The resulting material was characterized and packed in the tip by just pressing the material in the conical structure of the tip. This affinity tip established good and tunable permeability and was used to selectively enrich glycopeptides as well as phosphopeptides. The affinity tip demonstrated excellent performance to enrich glycopeptides and phosphopeptides with a low limit of detection up to 0.5 fmol μL−1 from tryptic digests of horseradish peroxidase and β-Casein, respectively, and was stable up to 5 rounds of enrichment. Moreover, this affinity-tip also exhibited high selectivity up to up to 1:1000 (HRP digest to BSA digest) for glycopeptides and 1:200 (β-Casein digest to BSA digest) for phosphopeptides and demonstrated several other fascinating characteristics such as; excellent size exclusion effect for the omission of large-sized proteins, modest backpressure, reproducibility, reusability, smooth enrichment, and successfully applied to a human saliva sample.

Phospholipids play a key role in infant nutrition and cognitive function. In this study, hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry method was firstly developed to analyze the composition of phospholipids. Then we characterized and quantified phospholipids extracted from raw, pasteurized, homogenized, and spray-dried milk to investigate the effect of the technological process on the composition of the phospholipids. Results indicate that the composition of the phospholipids underwent minor changes after pasteurization, while the concentration of phospholipids was significantly affected by the spray-drying process, especially phosphatidylethanolamine and phosphatidylinositol. Multivariate data analysis further verified the results and indicated that phospholipids containing polyunsaturated fatty acids had undergone significant changes during the production chain, especially in spray-drying. This work reveals the changes of phospholipids composition during the production chain of infant formulas and serve as a reference for the subsequent optimization of infant formulas to meet nutritional need of infants.

A clearer picture of interactions between differently coated silver nanoparticles (AgNPs) and biological interfaces that are confronted with by the dermal exposure route is of utmost importance for the risk assessment of various AgNP-based formulations utilized in the medical and dermocosmetic fields. This work sought to understand how surface modification of AgNPs, especially those produced by green synthesis strategy, affect the surface chemistry and dermocompatibility. Phytosynthetized AgNPs diverse in bio-reducing/capping agents i.e. chlorogenic acid, glycyrrhizic acid and gallic acid, were prepared by a bioinspired green approach and characterized in terms of size, shape, crystal phase, surface charge, structure and antioxidant activity. Chemically synthetized AgNPs stabilized by trisodium citrate or polyvinylpyrrolidone were also analyzed for comparison. The biological test results illustrate that varying coating material for AgNP stabilization results in differential toxicity against dermal microbes and HaCaT keratinocytes in vitro and affects dermal absorption through intact/compromised skin in vivo. Among all test samples, the citrate-stabilized AgNPs displayed the maximum cytotoxicity and dermal absorption. It is also of interest to note that the phytosynthetized AgNPs with chlorogenic acid exhibited superior antioxidant, attenuated cytotoxicity and minimal skin deposition, while those modified with glycyrrhizic acid demonstrated a preferentially antibacterial activity against the pathogenic (Escherichia coli and Staphylococcus aureus) over the beneficial bacterial strains (Staphylococcus epidermidis) inhabiting human skin. Furthermore, a percutaneous absorption of AgNPs into live epidermis was observed on all 7–13 nm sized AgNPs, irrespective of surface coating, with more pronounced skin deposition of silver species occurring for the chemically-synthetized AgNPs within compromised skin. Given all these results, it is concluded that surface modification with particular phytochemicals may render AgNPs with enhanced dermocompatibility or antimicrobial activity. This study provides a basis for risk assessments of phytosynthetized AgNPs in consumer products and suggests the possibility of tailoring AgNPs applicability via green chemistry approach.

Volatile organic compounds (VOCs) from solvent-based architectural coatings (SBACs) play an important role in photochemical air pollution with increasing consumption of architectural coatings in China. In this study, we collected 148 typical SBACs of 3 types in China. The TVOC emission factors and source profiles were established, the contributions of SBACs to ozone and secondary organic aerosol (SOA) formation were investigated. The VOC emissions and O3 and SOA amounts formed in chemical reactions from SBACs in 2017 were estimated. Key organic groups and VOC species with high reactivity were identified. According to the results, the TVOC emission factors were 507.17 g L−1 for solvent-based anticorrosive coatings, 381.34 g L−1 for solvent-based floor coatings and 459.68 g L−1 for solvent-based fire-retardant coatings. The VOC emissions were 186,902.11 t, 88,225.41 t and 71,352.32 t; the O3 amounts formed were 742,001.39 t, 397,896.60 t and 244,738.46 t; the SOA amounts formed were 3934.29 t, 2488.04 t and 1104.61 t, respectively, from 3 types of SBACs in 2017. The O3 production factors were 1781.82 g O3 (kg paint)−1, 1457.50 g O3 (kg paint)−1 and 1176.63 g O3 (kg paint)−1, the SOA production factors were 9.45 g SOA (kg paint)−1, 9.11 g SOA (kg paint)−1 and 5.31 g SOA (kg paint)−1, for 3 types of SBACs. Priority should be given to organic group of aromatics and top 17 VOC species with high reactivity for O3 and SOA eliminating strategies, especially three xylenes (o-xylene, m-xylene and p-xylene), ethylbenzene, trimethyl benzenes (1,3,5-trimethyl benzene, 1,2,3-Trimethyl benzene) and toluene.

Boronic acid-based affinity materials have gained tremendous attention for the selective separation and recognition of cis-diol containing biomolecules. But often, these boronate affinity materials are stuck to some serious issues like high binding pH and weak affinity, especially in the case of glycoproteins. Here in this study, we used 5-boronoisophthlic acid as a novel affinity ligand for the selective capture and release of glycoproteins. The pKa value of 5-boronoisophthalic acid is investigated to be 7.8 which is just closed to physiological pH and is ideally suitable for the fast binding and elution kinetics of glycoproteins to avoid their degradation and deactivation. The affinity ligand is attached to the surface of polymer support using branched polyethyleneimine (PEI) which enhances the binding strength as it has multiple amine groups available for the attachment of 5-boronoisophthalic for synergistic interactions. The resulting affinity material is characterized and packed in a micropipette-tip using hydrophilic melamine foam as a frit to make the separation process smooth, simple, reliable, and robust. This boronic acid-based affinity tip exhibits binding constants for model glycoproteins in the range of 10−6–10−7 M, binding capacities in the range of 0.662 μM/g, and selectivity up to 1:1000 (HRP to BSA) under optimized extraction conditions. Finally, the boronic-based affinity tip is successfully applied to selectively capture the glycoproteins from the human milk sample, especially lactoferrin which is highly important in dairy manufacture.

Biological activity and pharmacological efficacy of protein drugs may be affected by the compatibility between drug and packaging materials. The compatibility of rubber closures seal cap has become the focus of many studies due to its complicated formulation. Despite of the significance of the issue, currently, there is little available data about organic leachables in drugs which is also not comprehensive. Since the concentration of migrants in drug is usually low and the matrix is complicated, the establishment of overall profile of extractables is crucial for the characterization of leachables. Herein, the supercritical fluid extraction (SFE) method was used because of its great extraction capacity and efficiency for low to medium polar extractables in rubber stoppers. The SFE conditions were optimized by response surface methodology (RSM). Experimental results of the extract yield were close to the predicted values (R2 = 0.95). Then the extractables were qualitatively and quantitatively analyzed with ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS). Finally, risk assessment was made by comparing predicted exposure with injection permitted daily exposure (pPDE) limit or threshold recommended by threshold of toxicological concern (TTC). The results showed that there are many extractables such as glyceride, fatty acids and derivatives, antioxidants, and degradation products. Among them degradation products were in the majority and content of 17 substances exceeded corresponding limits. Considering their unknown toxicology, more experiments are therefore needed to provide information on their toxicology and risk assessment. The study provides a reference for the compatibility of drugs, and quality supervision of pharmaceuticals packaging.

Small molecules in food contact materials may migrate into food during their contact. To extensively analyze the migrants, non-targeted screening is needed to detect the migrants. The migrants’ detection is difficult because of the complexity and the trace amount of the migrants. In this work, the dissolution precipitation method was used to extract small molecules in Polyamide (PA) kitchenware. The extract solutions were screened by ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF-MS) for non-targeted analysis and 64 different small molecules in materials were identified through the screening of a self-built database. Then, migration tests were performed to analyze migrants in food simulants. It suggests that the abundance of PA oligomers was the highest in migrants. The risk assessment of migrants revealed that the exposure of most migrants was at a safer level unlike the exposure of PA oligomers that exceeded their threshold of toxicological concern (TTC).

RATIONALE Pentaerythritol fatty acid esters are an excellent lubricant oil additive, due to their good biodegradability, thermal ability, anti-wear, and friction properties. However, to meet the application requirements, fatty acids with different alkyl chain lengths are reacted with pentaerythritol, resulting in complex ester compositions. To reveal the relation between the functionalities and the composition of esters, it is important to develop a method for their analysis. METHODS We developed a method using ultra-high-performance supercritical fluid chromatography combined with quadrupole time-of-flight mass spectrometry (UHPSFC/QTOF-MS) to separate and characterize pentaerythritol fatty acid esters. This method has the advantages such as short analysis time and high separation efficiency for such weakly polar compounds; high-resolution mass spectrometry (HRMS) provides exact mass information, enabling the identification of the structure of the pentaerythritol fatty acid esters. RESULTS Based on the exact masses and characteristic ions, the pentaerythritol fatty acid esters and their main fragmentation pathways were identified; the fatty acid composition was also deduced from characteristic product ions. A dihydrogen rearrangement reaction caused the neutral loss of fatty acid fragment; [M + Na-FA]+ product ions (a stable six-member ring structure) were produced due to the absence of a γ hydrogen in pentaerythritol fatty acid esters. CONCLUSIONS A UHPSFC/QTOF-MS method was successfully employed for the separation of pentaerythritol fatty acid esters. Exact masses and product ion information were determined using HRMS. The composition of the fatty acids was effectively deduced by characteristic ions and their relative abundances. This method is an effective means for the quality control and process optimization of this type of product, serving as a positive reference for further study on pentaerythritol fatty acid esters.

Azithromycin (AZI) has been listed as an emerging contaminant by the US EPA since 2009 because it is frequently detected in wastewater, surface water, and drinking water. In this paper, the chlorination of AZI in drinking water was simulated and studied. The results indicated that new compounds were generated in the chlorination of AZI. The byproducts were identified by liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-Q-TOF), and four of the byproducts were detected in real water samples. The kinetic studies demonstrated that the reaction rates of AZI chlorination were dependent on the initial concentration of free chlorine and the pH value. The potential toxicities of the byproducts were assessed by quantitative structure-activity relationship software and investigated by the viability of Chinese hamster lung (CHL), Jurkat T and Hep G2 cells.

Cis-diol compounds are class of biomolecules including nucleosides, glycoproteins, saccharides, and nucleotides, which play vital roles in various biological processes. Due to low abundances of these species in the complex biological samples, their identification and analysis is difficult. Boronate affinity materials are commonly used for the isolation and enrichment of cis-diol compounds, due to their unique, facile and selective enrichment mechanism. In this study we report a selective approach to extract nucleosides, glycopeptides and glycoproteins using boronic acid functionalized GMA-MAA-DVB polymer. This novel polymer, reported for the first time in proteomics, have high BET surface area (132.8447 m2 g−1) which contribute to efficient enrichment and average pore size (20.3449 nm) to facilitates the nano confinement effect for strong interactions. Hydrophilic character of methacrylic acid and diethylenetriamine, along with inherent affinity of boronic acid for glycosylated biomolecules result in selectivity up to 1:500 for peptides and 1:1000 for glycoprotein. Binding constant for cis-diol compounds are in the range of 10−4 to 10−6 M and theoretical binding capacity up to 85 mg g−1 for HRP and 180 mg g−1 for IgG, respectively. Furthermore, boronic acid functionalized polymer (BFP) enrich glycoproteins and glycopeptides in range of 1 pg mL−1 and 0.04 ng mL−1 with S/N ≥ 3. Finally, material is applied to enrich the glycoproteins from healthy human saliva sample and six glycoproteins are identified.

Nitrogen doped TiO2 (N-TiO2) powders with different nitrogen doping dosages (urea) were prepared by sol gel method. Then, the powders were immobilized on the glass spheres by sodium silicate to improve its recyclability. The structure and morphological properties also were characterized. A common antibiotic ciprofloxacin (CIP) as water pollutant, was degraded to evaluate the photocatalytic activity of N-TiO2 immobilized on glass spheres. N-TiO2 sample with N/Ti weight ratio of 0.34% exhibits highest visible photocatalytic activity and the removal rate of CIP reached 90% in 90 min under visible light irradiation. The photocatalytic efficiency was hardly reduced after 5 cycle experiments, indicating that the recyclability of immobilized N-TiO2 was well. The kinetic model of degradation of CIP was confirmed as a first-order kinetic reaction model. The degradation products of CIP were analyzed by ultra-performance liquid chromatography tandem quadrupole time of flight mass spectrometry (UPLC-Q-TOF MS). A database containing 49 kinds of the degradation products of CIP already reported in the papers was established to screen the UPLC-Q-TOF MS results. 17 kinds of degradation products were found and the possible degradation pathways to CIP were inferred. The toxicological properties of these degradation products were assessed by computer software simulation. In this study, a new, simple and stable immobilization method was used to prepare N-TiO2 immobilized on glass spheres, and a rapid screening method for the degradation products of CIP was established.

Milk lipids are one of the most complex materials in nature and are associated with many physiological functions, hence it is important to comprehensively characterize lipids profiles to evaluate the nutritional value of milk. A quick method was developed by ultra-high performance supercritical fluid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (UHPSFC-ESI-QTOF-MS) to analyze the non-polar and polar lipids profiles of cow, goat, buffalo, human milk, and infant formulas in 7 min. All chromatographic conditions were carefully optimized and their effect on the chromatographic behavior of lipid classes and species was discussed. Under optimized conditions, 12 lipid classes (triacylglycerols, diacylglycerols, monoglyceride, fatty acids, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylglycerol, sphingomyelin, lyso-phosphatidylcholine, and lyso-phosphatidylethanolamine) were separated and each class was further separated in single analysis to facilitate the identification. 250 lipid species in real samples were characterized and quantified. This result demonstrates the applicability of the UHPSFC-ESI-QTOF-MS method in the high-throughput and comprehensive lipid analysis of milk, and will hopefully help to provide nutritionists with the lipid distribution in different types of milk, as well as help in the design of more suitable infant formula for babies.

Modern analytical techniques are playing increasingly important roles in archaeology. In the field of textile archaeology, the characteristics of silk and dyes are important since they may provide essential information on the origin of the material, dyeing techniques, and even historical windows in understanding trading routes of ancient textiles. Here, we first identify the ancient Chinese textiles from Qing Dynasty Royal Palace as silk fibroin by ATR-spectrum, then extraction conditions for dyestuff on textiles were evaluated as it have quite an effect on the analytical results in the chemical analysis, the extract was analyzed by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC-Q-Tof MS) to identify the natural dyes in these ancient textiles. The results showed that a gentle extraction method (MeOH/FA/EDTA) was efficient and berberine, flavonoids and indigo were identified simultaneously in extracts of ancient textiles by high-resolution mass spectrometry. By comparing extraction profiles of pigments in plants as the likely dye sources by UHPLC-Q-TOF MS, we identified Sophora japonica L. and Phellodendron amurense Rupr. as the dye sources in historical silk fibres. The analyses suggest that the bright yellow textiles were likely dyed with a combination of these two plants and aluminium was used as mordant in the dyeing process. The experiment of color restoration confirmed our analysis. This study demonstrated its ability to identify the dyeing technology of ancient China and provide valuable data for the reparation of historical textiles preserved in the Palace Museum, Beijing.

Hyperuricemia caused by purine metabolic abnormalities is reported to have close correlation with lipid metabolic disorders. Ginkgo folium, a frequently-used lipid-lowering medicine, has significant anti-hyperuricemia effects. However, it is poorly known about the interaction between lowering uric acid and regulation of lipid metabolic disorders. In this study, hyperuricemic rat model was induced by orally administration with fructose. Ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) combined with pattern recognition approaches were used to determine different lipid metabolites in serum of control group, model group, and different doses of ginkgo folium groups. Principal component analysis (PCA) was applied to analyze the MS data to assess the establishment of model, partial least squares-discriminate analysis (PLS-DA) and independent samples T-test were performed to indicate the differences between different groups of rats and to find biomarkers. Metabolomics pathway analysis (MetPA) was introduced to reveal the pharmacologic mechanisms of ginkgo folium. 19 potential biomarkers associated with hyperuricemia were found. After intervened by ginkgo folium, these biomarkers were returning to normal level. Among these biomarkers, 13 lipid biomarkers were significantly reversed. Ginkgo filum can lower uric acid via adjusting back the level of PCs and LPCs, which suggested that its treatment mechanisms may be related to reducing the activity of PLA2. In sum, the lipidomics analysis in the system level have enhanced our understanding to pathogenesis of hyperuricemia and the results suggested that ginkgo folium could alleviate the abnormal metabolic status of hyperuricemia. These results demonstrated a new mechanism for lowering uric acid, which was helpful to the early treatment for hyperuricemia.

Triacylglycerols (TAGs) as the major component of milk fat are significant factors to ensure the healthy growth of infants. An efficient method for identifying TAGs in human milk (HM) and infant formula (IF) was established using supercritical fluid chromatograph (SFC) coupled with quadruple time-of-flight mass spectrometry (Q-TOF-MS). The results indicated the feasibility of this method with satisfactory recoveries (>80%) and correlation coefficients (r2⩾0.993). More than 60 TAGs in HM and 50 TAGs in IF were identified. The profiling results demonstrated that TAGs in HM were greatly affected by lactation stage. Significant differences were found between HM and IF, such as much higher medium chain TAGs and saturated TAGs in IF, indicating that the formulas developed by foreign manufacturers were not suitable for Chinese babies. This high-throughput method exhibits a huge potential for analysis of milk samples and the result may serve as an important guide for Chinese infants diet.

A method employing a type of filtered solid phase extraction based on the PRiME hydrophilic lipophilic balance (HLB) was developed for extracting cephalosporin compounds (cephalexin monohydrate, cefradine, cefazolin, cefotaxime, cefmenoxime, cefoperazone sodium, cefadroxil, cefpirome sulfate, cefquinome sulfate, cefaclor, ceftizoxime, cephalonium, cephalothin sodium, cefamandole lithium, cefathiamidine, cefetamet pivoxyl) from milk samples. Compared to conventional HLB extraction, the PRiME HLB SPE process consists of only one step without activation, elution. It shows the advantage of a faster and better purifying capacity. Ultra-high pressure liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) was used for detection. In order to obtain high recoveries of the analytes, several parameters were optimized, such as variation of the extraction solvents, and the volume of the extraction solvent and dripping washing solution. With an optimized sample preparation, the limit of detection (LOD) and limit of quantification (LOQ) for the multi-reaction-monitoring (MRM) mode of the method varied from 0.02 to 5 μg kg−1, and 0.02 to 10 μg kg−1, respectively. Due to the different sensitivities of the analytes, the calibration curves were linear with R2 ≥ 0.991 in their linear ranges. The relative recoveries from the milk samples were between 56% and 93% with relative standard deviations lower than 15%.

The supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) method and liquid chromatography coupled with mass spectrometry (LC-MS) method were developed for the separation and characterization of poly (ethylene oxide) methyl glucose sesquistearate (PEO-Glu-sesquistearate). The products of PEO-Glu-sesquistearate are composed of complex oligomers. The relationship between molecular structure of these oligomers and chromatographic retention behavior in both SFC and LC were discussed and compared. As compared with LC, hydrophobic moieties of compounds favor the fast elution in SFC. The different series can be better separated by LC, while the homologues compounds in same series can be better separated by SFC, and SFC-MS provided more comprehensive structural information. Different series such as PEO-distearate, PEO-stearate, PEO, PEO-Glu-tetrastearate, PEO-Glu-tristearate, PEO-Glu-distearate, PEO-Glu-stearate, and PEO-Glu were identified by MS/MS.

In this study, a reliable and novel coupling of pipette-tip micro-solid phase extraction (PT-µSPE) with corona discharge ionization-ion mobility spectrometry (CD-IMS) was developed for on-site fast detection of benzodiazepines (BZDs) in dietary supplements. The poly (styrene-co-divinylbenzene) (St-co-DVB) monoliths fabricated in pipette-tips through an in-situ polycondensation reaction. The extraction procedure of PT-µSPE for aqueous sample was performed for an appropriate number of aspirating/dispensing cycles by using a manual micropipettor. Then analytes retained in the polymeric monoliths were eluted with elution solvents by repeating the aspirating/dispensing cycles, and the eluates were analyzed by CD-IMS. In order to find the best extraction conditions, several parameters such as the number of aspirating/dispensing cycles for extraction and desorption, pH, elution solvent, amount of polymer and ionic strength were investigated. Under the optimal conditions, the LOD of this method was in the range of 5–15 ng mL−1. The spiked recovery values in real sample were obtained by PT-µSPE-IMS in the range of 84.2–112.1% and validated by ultraperformance liquid chromatography tandem mass spectrometry (UPLC–MS/MS). PT-µSPE as an on-site sampling method can be suitably combined to IMS which has great potential to achieve high throughput detection by using a multichannel micropipette. The satisfactory analytical results reveal that the developed method can be effectively applied for on-site screening BZDs in health products.

A method based on gas chromatography coupled with triple quadrupole mass spectrometry (GC–MS/MS) combined with QuEChERS extraction was developed to detect furfurals, including furfural, 2-acetylfuran, 5-methyl-2-furfural, and 5-hydroxymethyl-2-furfural, in milk-based dairy products. Under the optimized conditions, good linearity was obtained with correlation coefficients (R2) above 0.999, and the recovery values from the spiked samples were 79.0%–115.0% with relative standard deviations (RSDs) less than 13.1%. The limits of detection (LODS) were in the range of 0.002–0.02 mg/kg. To investigate the effects of the production process on milk-based dairy products, 55 real samples were analysed. The higher contents of furfurals were observed when higher temperatures were used during heat treatment and fermentation. In addition, the Toxtree and T.E.S.T. software programs were used to predict the risks associated with these four furfurals. Ultimately, safe dairy intake levels were determined.

A new method was established for the determination of the extractables from pharmaceutical packaging materials using dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME-SFO) coupled with ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS). Packaging samples were filled with three kinds of buffer solutions: acid buffer (pH = 3), alkaline buffer (pH = 9) and 0.9% NaCl solution to extract as many extractables as possible, and then the extractables in buffer solutions were enriched by DLLME-SFO technique. Parameters affecting the efficiency of the extraction procedure were evaluated and optimized, including the type and volume of dispersant, extractant volume, pH and vortex-mixing time. After optimization, the values obtained for limits of detection and quantification for three kinds of common antioxidants were 0.3 and 1.0 μg/L respectively, and good linearity (R2 > 0.99) was observed in their respective concentration ranges. The recoveries ranged from 80.61% to 117.87% at three spiked levels with the relative standard deviations (RSDs) between 0.92% and 9.29% (n = 6) in all three buffer solutions. The developed method was successfully applied to the analysis of extractables from pharmaceutical packaging materials. The results indicated that the proposed procedure is a novel, sensitive, fast and repeatable method and has a great significance for evaluation of safety of pharmaceutical packaging materials.

Sudan dyes are one kind of synthetic azo dyes that are forbidden to use in foodstuffs according to the European Union Rule. In this work, considering the structure of Sudan dyes, nickel-foam@polydopamine (NF@PDA) was prepared through the self-polymerization of dopamine on the nickel-foam surface under weak alkaline conditions and used as SPME material to selectively extract the Sudan dyes. With the feature of three dimension (3D) cross-linked grid structure, large porosity and specific surface area, Ni-foam was selected as carrier material which can increase mass adsorption capacity. The primary parameters affecting extraction efficiency such as extraction time, extraction temperature, stirring speed, pH value, ionic strength and desorption time were investigated and optimized. After the Sudan dyes were eluted from the NF@PDA, the eluate was detected by IMS with a corona discharge (CD) ionization source. Thus, an innovative and rapid screening method coupling the NF@PDA to ion mobility spectrometry (IMS) was developed. Under the optimal extraction conditions, the detection limits for Sudan dyes were in the range from 0.005 μg g-1 to 0.25 μg g-1. The spiked recoveries were in the range from 81% to 91.3% by testing tomato sauce and hot-pot sample and validated by the UPLC-MS. Based on the results, the PDA coating has great ability for the extraction of Sudan dyes, mainly due to the catechol structure, electron-deficient quinones and amine groups on its surface. Thus, the developed method has great potential for on-site rapid screening of the Sudan dyes in food quarantine field.

Endogenous glycopeptides are significantly important in diverse pathological and physiological systems, but their direct analysis is severely hampered by their low abundance and presence of interfering species in biological fluids. In this study, we synthesized the amine-functionalized titanium metal-organic framework (NH2-MIL-125(Ti)) by a simple hydrothermal method, characterized and used for glycopeptides enrichment. The designed separation media is highly hydrophilic and stable which is suitable for hydrophilic interaction chromatography (HILIC). To make the process smooth, simple, reliable, and robust, NH2-MIL-125(Ti) crystals were packed in pipette-tip using hydrophilic melamine foam, as supporting frit. Free amine groups, present in the structure imparted hydrophilicity and a unique pattern of porosity, contributing to the size exclusion effect that excluded the large-sized proteins up to 1:700 peptide to protein ratio. The prepared MOF particles possessed regular porosity, high surface area, good hydrophilicity, and offered an in-tip flow-based set-up enhanced the enrichment performance for N-linked glycopeptides. The affinity material showed a detection limit of 1 fmol.µL-1 and selectivity up to 1:1000 (HRP digest to BSA digest). Moreover, repeatability and reusability were evaluated up to five rounds of enrichment using the same affinity tip, and scanning electron microscopic images revealed no structural changes in the MOF crystals. Finally, the MOF packed in pipette tip was applied to selectively capture the N-linked endogenous glycopeptides from a healthy saliva sample and 64 unique endogenous glycopeptides were identified. These results demonstrated the excellent potential of NH2-MIL-125(Ti) based affinity tip for glycopeptides which can be used to enrich trace glycopeptide biomarkers from the biological fluids.

UV-ink photoinitiators (PIs), which are used to initiate polymerization reaction for the curing of inks and lacquers, have become a kind of contaminant residues in printing plastic food packaging. The residual PIs in packaging may pose a potential threat to customers. In this work, migration behaviors of 13 PIs from a polyethylene (PE) packaging to food simulants according to regulation EU No 10/2011 were studied by supercritical fluid chromatography combined with photodiode array detector and tandem mass spectrometry (SFC-PDA-MS/MS). The method simultaneously analyzed 13 PIs within 4.5 min and was sensitively with low limits of detection of 0.02–2.16 μg/L, which could meet high throughput analysis for control the quality of food packaging. The migration results revealed that Irgacure 819, Darocure 1173 and TPO, which had low migration rates, should be preferably selected by plastic food packaging manufacture for food safety.

The direct contact of plastic parts with the medical products raises the possibility that plastic-related contaminants (leachables) may be present in the finished medical product. The leachable components from plastic materials may impact the safety and efficacy of the final medical product, so identification and determination of the leachables are essential for the safety assessment of medical products. A method to identify main leachables-polymer additives in medical products was developed by ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF MS) and a self-built library. The library contains 174 additives and the information on their names, formulas, structures, retention times, fragments, classifications, origin, and corresponding MS(E) and MSMS spectra. The reliability of the construction process of the library was guaranteed by the system stability and suitability test. Identification parameters of library application, such as mass error, retention times, fragments, and isotope pattern, were evaluated. Leachables in real vaccine and the intermediates were identified using automatic library searching. In vaccine, the peak m/z 239.0887 that could not be assigned by the library was identified as dimethyl 2-hydroxy-1,3-cyclohexanedicarboxylate using a series of elucidation tools. As a result, the concentrations of leachables in vaccine and the intermediates ranged from 0.85 to 21.91 μg/L.

Triacylglycerol (TAG) as the major ingredient of oil is a key indicator for the identification of oil adulteration due to its characteristic distributions in different oils. In this research, a high-throughput method for rapidly detecting acylglycerols in various edible oils was established by applying supercritical fluid chromatography (SFC) coupled with quadruple time-of-flight mass spectrometry (Q-TOF-MS), without any sample pretreatment procedure. The retention mechanism of TAGs on different columns were comprehensively evaluated including the previous work on an ODS column, as well as our study on HSS C18SB, BEH and BEH 2-EP columns. Distinctive retention of our method allows the separation of certain pairs of TAGs which remains difficult by traditional methods, and the analysis time is greatly reduced. SFC-MS data were subsequently analysed by principal component analysis (PCA) to make a clear classification between six different kinds of vegetable oils, showing its potential in differentiating the fakes quickly. Considering the high-price of olive oil, further quantification of olive oil adulteration was studied by estimating known and unknown compositions of blend oils according to the curves of areas of selected TAG markers versus adulterant concentrations. Good consistencies with the labeled content of olive oil in commercial blend oils demonstrated the reliability of the quantitative method, and these blend oils were differentiated distinctly from pure olive oils in the score plot of a PCA model. To the best of our knowledge, it was the first time that the retention of TAGs using different stationary phases in a SFC system was discussed, and that SFC was applied to quantify oil adulteration. This fast and effective method is of great advantage to authenticate edible oils.

In this study, the occurrence, seasonal, and spatial variations of four classes antibiotics were investigated in the surface water of North China. Water samples were taken from 24 sampling sites along rivers in May and August and antibiotics in water samples were detected by SPE-UPLC-MS/MS. The occurrence of all antibiotics except for FLO in May were higher than in August. The mean concentrations of four classes antibiotics detected in May and August were in the following order respectively: quinolones (421.23 ng/L) > tetracyclines (28.37 ng/L) > amphenicols (20.38 ng/L) > sulfonamides (5.79 ng/L) and amphenicols (284.36 ng/L) > quinolones (15.74 ng/L) > tetracyclines (3.05 ng/L) > sulfonamides (0.20 ng/L). The results showed that quinolones and amphenicols were dominant antibiotics among four classes antibiotics. To explore the source of antibiotics from the fish ponds nearby, antibiotic concentration data, which was investigated in the sediment, fish feed and fish revealed a direct relationship between the main antibiotics and fish farms along the rivers. Risk assessment data indicated enrofloxacin and florfenicol could cause higher safety risks to aquatic organisms compared to other antibiotics.

Comprehensive separation and analysis of non-ionic surfactants have been conducted by coupling supercritical fluid chromatography (SFC) with ion mobility spectrometry-mass spectrometry (IMS-MS). Representative non-ionic surfactants were investigated, including alkylphenol ethoxylates (APEOs), e.g., octylphenol ethoxylates (OPEOs) and fatty alcohol ethoxylates (FAEs), e.g., lauryl alcohol ethoxylates (LAEs). A sub-2-μm high-density diol column was used for chromatographic separation by the first-dimensional SFC due to the differences in ethoxy chain prior to electrospray ionization (ESI). Maintaining the fidelity of pre-ionization separation in the first dimension, the introduction of IMS provided additional post-ionization resolution by broadly fractionating the oligometric ethoxymers based on their size and electric charge within 13.78 ms. Distinguishable series of singly and multiply charged non-ionic species could be clearly observed. The millisecond timescale ion mobility separation perfectly fits the elution time of a chromatographic peak, while effectively feeding components into the fast-scanning time-of-flight (TOF) mass analyzer for characterization and analysis. The orthogonality of the developed separation and analysis system was evaluated, revealing a correlation coefficient and peak spreading angle of 0.2729 and 74.16° for the studied OPEOs and 0.1962 and 78.69° for LAEs. Significant enhancement in peak capacity was achieved for the developed SFC-IMS-MS system with the actual peak capacity measured to be approximately 41 and 160 times higher than that of the dimensions of SFC and IMS, respectively, when used alone. Graphical abstract.

An easy-to-use method for determining the levels of fipronil and its metabolites (fipronil-desulfinyl, fipronil-sulfone and fipronil-sulfide) in chicken egg, muscle and cake was developed and validated using a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) approach coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The samples were extracted using acetonitrile, salted out with sodium chloride at −20°C, and then purified by combined PSA and C18 phases and anhydrous magnesium sulphate. The recoveries were 80.4–119% with relative standard deviations (RSDs) < 10% for the different matrixes. The validated method was used to analyse the target compounds in 214 real samples collected in Beijing. The metabolite fipronil-sulfone was detected in most of the samples and was identified as the main residue in the egg and cake. The method was validated using a proficiency test for fipronil in products of animal origin published by Wageningen University & Research in 2017.

Determination of free fatty acids (FFAs) in food products is of enormous interest mainly because they are related to the quality and authenticity of the oils. In this study, supercritical fluid chromatography (SFC), followed by an electrospray ionisation triple-quadrupole mass spectrometry (ESI-MS), is shown to provide a novel method for the separation and detection of FFAs in edible oils without any pretreatment. Eight FFAs were separated on a HSS C18 SB column with gradient elution within 3 min. Effects of different columns, modifiers and column temperature changes were evaluated. The results indicated the feasibility of this method for the high-throughput determination of individual FFAs with satisfactory correlation coefficients (R(2)>0.994) and good reproducibility of RSD