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The quantification of allergens in food including baked food matrices is of great interest. The aim of the present study was to describe a non-immunologic method to quantify bovine β-casein using ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-TQ-MS/MS) in multiple reaction monitoring (MRM) mode. Eight of 10 theoretical peptides from β-casein after tryptic digestion were compared and MRM methods were developed to determine five signature peptides. The peptide VLPVPQK was selected as the signature peptide for bovine β-casein because of the high sensitivity. A stable isotope-labelled internal standard was designed to adjust the instability of sample pre-treatment and ionisation caused by matrix effect. Using the present suspension digestion method, the native and denatured β-casein could be digested to release the signature peptide at the maximum extent. The UPLC-TQ-MS/MS method developed based on a tryptic signature peptide led to a reliable determination of bovine β-casein allergen in baked food matrices at a low quantitation level down to 500 μg kg–1with a satisfactory accuracy (< 8.9%) and recovery (98.8% ± 2.6% to 106.7% ± 3.0%). [ABSTRACT FROM AUTHOR]

A method was developed for simultaneous determination of 5'-monophosphate nucleotides, adenosine 5'-monophosphate, cytidine 5'-monophosphate, guanosine 5'-monophosphate, inosine 5'-monophosphate, and uridine 5'-monophosphate in infant formulas by high-performance liquid chromatography-mass spectrometry equipped with electrospray ionization source. The complete chromatographic separation of five nucleotides was achieved through a Symmetry C18column, after a binary gradient elution with water containing 0.1% formic acid and acetonitrile as mobile phase. The multi-reaction monitoring mode was applied for tandem mass spectrometry analysis. The established method was further validated by determining the linearity (R2> 0.999), recovery (92.0–105.0%), and precision (relative standard deviation ≤6.97%). To verify the applicability of the method, thirty commercially available infant formulas were randomly purchased from the supermarkets in Hangzhou, China, and then analyzed. The results showed that the developed method is validated, sensitive, and reliable for quantitation of nucleotides in infant formulas. [ABSTRACT FROM AUTHOR]

• UHPLC-MS/MS method was applied to detect casein glycomacropeptide in dairy products. • Characteristic peptide was qualitatively confirmed by high-resolution mass spectrometry. • Labeled amino acid condensation method was used to get isotope-labeled characteristic peptides. • The oxidation conditions (oxidant concentration, temperature, and time) were optimized. The ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS) method was built to quantify the casein glycomacropeptide (CGMP) in bovine dairy products accurately based on targeted proteomics. Qualitative analysis of theoretical peptides was carried out using high-resolution mass spectrometry (HRMS) and protein software. Isotope-labeled characteristic peptides were acquired via the labeled amino acid condensation method to correct the matrix effects. Peptide MAIPPK was the representative characteristic peptide for distinguishing the CGMP from κ -casein through trypsin digestion. After optimizing the pre-treatment conditions, the final 8% oxidant concentration was selected and the 10% formic acid concentration with 2.5 h oxidation time. Moreover, the results of methodological verification showed that the recovery rate was 103.7%, meanwhile the precision of inter-day and intra-day was less than 5%. In conclusion, the research demonstrated the characteristic peptide MAIPPK could quantitatively applied to detect CGMP in dairy products. [ABSTRACT FROM AUTHOR]

[Display omitted] • We proposed a reliable pipeline for screening new indoor chemicals utilizing GC × GC. • The addressed organics are all intermediate volatility organic compounds (IVOCs). • Partition properties of organics are evaluated by pixel-based approaches. Indoor pollutants change over time and place. Exposure to hazardous organics is associated with adverse health effects. This work sampled gaseous organics by Tenax TA tubes in two indoor rooms, i.e., an office set as samples, and the room of chassis dynamometer (RCD) set as backgrounds. Compounds are analyzed by a thermal desorption comprehensive two-dimensional gas chromatography-quadrupole mass spectrometer (TD-GC × GC-qMS). Four new chemicals of emerging concern (CECs) are screened in 469 organics quantified. We proposed a three-step pipeline for CECs screening utilizing GC × GC including 1) non-target scanning of organics with convincing molecular structures and quantification results, 2) statistical analysis between samples and backgrounds to extract useful information, and 3) pixel-based property estimation to evaluate the contamination potential of addressed chemicals. New CECs spotted in this work are all intermediate volatility organic compounds (IVOCs), containing mintketone, isolongifolene, β -funebrene, and (5 α)-androstane. Mintketone and sesquiterpenes may be derived from the use of volatile chemical products (VCPs), while (5 α)-androstane is probably human-emitted. The occurrence and contamination potential of the addressed new CECs are reported for the first time. Non-target scanning and the measurement of IVOCs are of vital importance to get a full glimpse of indoor organics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of material preparation methods and devices is essential for electrochemical nitrogen immobilization. • Plasma etching technique to construct highly enriched oxygen vacancy ZrO 2 anchored Ru single atoms. • The utilization of flow cell technology greatly enhances its Faradaic efficiency. Ammonia is an important raw material for chemical, fertilizer, and energy storage. Energy-intensive industrial nitrogen fixation goes against the carbon–neutral concept and needs to be replaced by clean alternative electrochemical nitrogen fixation methods (ENF). Herein, we report a single-atom Ru loaded on MOF-derived oxygen-rich vacancies ZrO 2 porous carbon material (Ru@ ZrO-PL) by plasma etching technique to enhance the ENF properties with the NH 3 yield rate of 83.1 ± 2.4 μg h−1 mg cat −1 and the Faradaic efficiency (FE) of 13.8 ± 0.4 at −0.25 V vs RHE. The advanced flow cell device improves the efficiency of material transfer and greatly enhances the ENF properties of the Ru@ ZrO-PL, with an NH 3 yield rate up to 113.1 ± 6.5 μg h−1 mg cat −1 and FE up to 57.3 ± 2.9% at −0.20 V vs RHE. Theoretical calculations revealed that the single-atom Ru embraced by the oxygen-rich vacancy ZrO 2 porous carbon enhanced the N 2 adsorption activation, which was more favorable for the ENF process. This work provides new ideas for enhancing the ENF performance of single-atom materials and highlights the advantages of novel devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The AGEs formation mechanism in milk and dairy products are analyzed. • The composition, processing and storage condition can effect AGEs formation. • AGEs inhibition strategies are comprehensively summarized. • RAGE/MAPKs/NF-κB, AGE-R1/SIRT1 and LOX-1 can activate AGEs-mediated pathway. • AGEs modulate immunometabolism and gut-brain axis via gut microbiota. Advanced glycosylation end products (AGEs) are a series of complex compounds which generate in the advanced phase of Maillard reaction, which can pose a non-negligible risk to human health. This article systematically encompasses AGEs in milk and dairy products under different processing conditions, influencing factors, inhibition mechanism and levels among the different categories of dairy products. In particular, it describes the effects of various sterilization techniques on the Maillard reaction. Different processing techniques have a significant effect on AGEs content. In addition, it clearly articulates the determination methods of AGEs and even discusses its immunometabolism via gut microbiota. It is observed that the metabolism of AGEs can affect the composition of the gut microbiota, which further has an impact on intestinal function and the gut-brain axis. This research also provides a suggestion for AGEs mitigation strategies, which are beneficial to optimize the dairy production, especially innovative processing technology application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Swellable bi-functional poly(ionic liquid)s (BF-PILs) containing ionic liquid species and basic group were constructed. • The adjustable swelling ability facilitated mass transfer and sufficient contact between reactants and BF-PILs. • BF-PILs exhibited excellent catalytic activity for the CO 2 -promoted hydration of EO at a low H 2 O/EO ratio of 1.5:1. The highly selective production of monoethylene glycol (MEG) from ethylene oxide (EO) is desirable at low H 2 O/EO molar ratio, however, the development of an efficient heterogeneous catalyst for the reaction is a challenge. Herein, a series of bi-functional poly(ionic liquid)s (BF-PILs) were successfully synthesized by radical copolymerization of polymerizable phosphonium/ammonium ionic liquids, N-vinyl imidazole and cross-linker divinylbenzene (DVB). The structure and thermal stability of BF-PILs were characterized by NMR, FT-IR, elemental analysis and TGA. These BF-PILs could be swollen in the H 2 O and MEG mixture and the swelling ratio (Q) increased with the increase of the MEG mole fraction. Under swelling in the H 2 O and MEG mixture (1:1), BF-PILs presented an irregular channel structure with the diameter of 1–20 μm observed by the cryo-scanning electron microscope (cryo-SEM). BF-PILs were applied to catalyze the CO 2 -promoted hydration of EO at a low H 2 O/EO ratio of 1.5:1. The catalytic activities of phosphonium BF-PILs were superior to ammonium BF-PILs, and poly[(Ph) 3 VBPBr-VIm] with the greatest Q in the H 2 O and MEG mixture (1:1) gave highest yield (96.1%) and selectivity (97.3%) of MEG. The CO 2 -promoted hydration of EO involved the cycloaddition of EO with CO 2 to produce ethylene carbonate (EC), and followed by the hydrolysis of EC to produce MEG. Kinetic experiments confirmed that phosphonium ionic liquid species mainly catalyzed CO 2 cycloaddition and imidazole catalyzed hydrolysis of EC. Furthermore, poly[(Ph) 3 VBPBr-VIm] exhibited good generality and could be reused up to eight times without significant decrease of its initial activity. [ABSTRACT FROM AUTHOR]

• UPLC-MS/MS method was established for determination of acrylamide. • Acrylamide in samples was cleaned up by single-step SPE using mixed-mode sorbents. • Retention capability and resistance to interference was improved by derivatization. • Efficiency of acrylamide derivatization was improved under an acidic condition. • The method is suitable for the determination of acrylamide in coffee its products. This work aimed to establish a novel determination method for acrylamide in coffee and its products by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Acrylamide in samples were prepared by a single-step solid-phase extraction clean-up using mixed mode sorbents. The bromine derivatization efficiency of acrylamide and its internal standard were improved at an acidic condition. After derivation, the retention capability of acrylamide and its resistance to interference were significantly improved. The limit of detection (LOD) and the limit of quantification (LOQ) were 1.2 and 4 μg/kg for roasted and instant coffees, while they were 0.24 and 0.8 μg/kg for ready-to-drink coffees. The average recoveries for acrylamide ranged from 99.3 to 102.2% in coffee and its products. All the results showed that the developed method was simple, quick, specific and suitable for screening and determination of acrylamide in batch samples of coffee and its products. [ABSTRACT FROM AUTHOR]

The article presents a study which determined the total choline by liquid chromatography in infant formulas. Choline is a water-soluble nutrients significant for the brain and neural development of infants and is one of the most significant fortified nutrients. It concluded that the method was found to be highly credible and can be used as a routine method of quality control.

Coordination cages have been widely reported to bind a variety of guests, which are useful for chemical separation. Although the use of cages in the solid state benefits the recycling, the flexibility, dynamicity, and metal-ligand bond reversibility of solid-state cages are poor, preventing efficient guest encapsulation. Here we report a type of coordination cage-integrated solid materials that can be swelled into gel in water. The material is prepared through incorporation of an anionic Fe II 4 L 6 cage as the counterion of a cationic poly(ionic liquid) (MOC@PIL). The immobilized cages within MOC@PILs have been found to greatly affect the swelling ability of MOC@PILs and thus the mechanical properties. Importantly, upon swelling, the uptake of water provides an ideal microenvironment within the gels for the immobilized cages to dynamically move and flex that leads to excellent solution-level guest binding performances. This concept has enabled the use of MOC@PILs as efficient adsorbents for the removal of pollutants from water and for the purification of toluene and cyclohexane. Importantly, MOC@PILs can be regenerated through a deswelling strategy along with the recycling of the extracted guests., (© 2024. The Author(s).)

Polypeptide N-Acetylgalactosaminyltransferase (GALNTs) are critical enzymes that initiate mucin type-O glycosylation, and are closely associated with the occurrence and development of multiple cancers. However, the significance of GALNT2 in clear cell renal cell carcinoma (ccRCC) progression remains largely undetermined. Based on public multi-omics analysis, GALNT2 was strongly elevated in ccRCC versus adjoining nontumor tissues, and it displayed a relationship with poor overall survival (OS) of ccRCC patients. In addition, GALNT2 over-expression accelerated proliferation of renal cancer cell (RCC) lines. In contrast, GALNT2 knockdown using shRNAs suppressed cell proliferation, and this was rescued by LATS2 knockdown. Similarly, GALNT2 deficiency enhanced p-LATS2/LATS2 expression. LATS2 is activated by phosphorylation (p-LATS2) and, in turn, phosphorylate the downstream substrate protein YAP. Phosphorylated YAP (p-YAP) stimulated its degradation and cytoplasmic retention, as it was unable to translocate to the nucleus. This resulted in reduced cell proliferation. Subsequently, we explored the upstream miRNAs of GALNT2. Using dual luciferase reporter assay, we revealed that miR-139-5p interacted with the 3' UTR of GALNT2. Low miR-139-5p expression was associated with worse ccRCC patient outcome. Based on our experiments, miR-139-5p overexpression inhibited RCC proliferation, and this phenotype was rescued by GALNT2 overexpression. Given these evidences, the miR-139-5p-GALNT2-LATS2 axis is critical for RCC proliferation, and it is an excellent candidate for a new therapeutic target in ccRCC., (© 2024. The Author(s).)

NH 3 is an essential ingredient of chemical, fertilizer, and energy storage products. Industrial nitrogen fixation consumes an enormous amount of energy, which is counter to the concept of carbon neutrality, hence eNRR ought to be implemented as a clean alternative. Herein, we propose a double-single-atom MoCu-embedded porous carbon material derived from uio-66 (MoCu@C) by plasma-enhanced chemical vapor deposition (PECVD) to boost eNRR capabilities, with an NH 3 yield rate of 52.4 μg h -1 g cat. -1 and a faradaic efficiency (FE) of 27.4%. Advanced XANES shows that the Mo active site receives electrons from Cu, modifies the electronic structure of the Mo active site and enhances N 2 adsorption activation. The invention of rational MoCu double-single-atom materials and the utilization of effective eNRR approaches furnish the necessary building blocks for the fundamental study and practical application of Mo-based materials.

Objective: To establish a rapid and accurate method for the determination of cholesterol in a variety of finished dishes., Methods: The samples were saponified with ethanol and potassium hydroxide solution at 80 ℃ for 0.5 h, then vortexed and mixed fully with ultrapure water, and extracted twice with 25 mL n-hexane. The extracting solution were evaporated to dryness under vacuum and redissolved by ethanol, finally determined by gas chromatograph. The sample loading solution was separated by HP-5 capillary column(30 m×0.25 mm, 0.25 μm) and quantified with external standard method., Results: The method had good linearity in the concentration range of 2.5-250 μg/mL for cholesterol and the correlation coefficient was 0.9999. The detection limit was 0.25 mg/100 g edible part, and the limit of quantification was 0.75 mg/100 g edible part. Three representative samples were picked for spiked recovery experiments with three concentration levels according to their content of cholesterol. The average recovery rates ranged from 91.1% to 101%, and the relative standard deviations were not more than 5%. The content range of cholesterol in 15 vegan dishes was from negative to 10.3 mg/100 g edible part, in 14 dishes contained meat and vegetable was from 2.34 to 80.2 mg/100 g edible part and in 9 pure meat dishes was from 25.4 to 288 mg/100 g edible part., Conclusion: Compared with the national standard method, the method is simple to operate and more friendly to the experimenter while ensuring the accuracy and sensitivity requirements. It can meet the needs of efficient batch determination of cholesterol in a variety of finished dishes.

Swelling is a very common phenomenon in organic substances. However, the swelling behaviors of inorganic substances had rarely been reported. In this study, a new type of swellable organic-inorganic hybrid polymer (PIL@CHT) was designed and successfully synthesized through free-radical copolymerization of polymerizable phosphonium ionic liquid monomer and vinyl-functionalized hydrotalcite (CHT). The swelling behaviors of PIL@CHT in various solvents with a wide range of Hansen solubility parameters (δ T ) were investigated, and PIL@CHT exhibited excellent swellable capacity in the solvents with δ T > 24.4 MPa 1/2 . The swollen state of the hybrid PIL@CHT in water presented a network structure with a diameter of approximately 8-12 μm, and CHT particles were well dispersed to the channel of PIL. PIL@CHT was applied to catalyze the CO 2 -assisted hydration of propylene oxide (PO), in which a cascade reaction including the cycloaddition of CO 2 and PO and the subsequent hydrolysis of propylene carbonate (PC) occurred. PIL@CHT, combining the active sites of PIL and CHT, synergistically catalyzed this cascade reaction and achieved a high yield (93.0%) and selectivity (98.2%) of 1,2-propanediol (1,2-MPG) under a low H 2 O/PO ratio of 1.5/1. Moreover, the catalyst could be recycled seven times without any significant loss of catalytic activities and had good substrate generality.

Objective: To establish a method for the simultaneous determination of vitamins A, D and E in dishes by two-dimensional liquid chromatography., Methods: The samples were saponified and extracted with a mixture of ethyl acetate and n-hexane(3∶2, V/V)under the protection of antioxidants, and determined by two-dimensional liquid chromatography. The baseline separation of retinol, α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol, and α-tocotrienols was achieved by using Alphasil pentafluorophenyl column(PFP, 150 mm×4.6 mm, 5 μm) as the one-dimensional column, and using water and methanol as mobile phases for gradient elution under the fluorescence detector. The separation detection of ergocalciferol and cholecalciferol from other impurities was achieved on the UV detector by Alphasil VC-C&#95;(18) column(150 mm×4.6 mm, 3.5 μm) as the two-dimensional column., Results: The baseline separation detection of retinol, ergocalciferol, cholecalciferol and five tocopherols was achieved. The compounds were linearly correlated within the set range, and the correlation coefficients were &gt;0.999. The recovery rate of the method was between 85.4% and 106.4%. The detection limit of all-trans retinol was 0.7 μg/100 g, and the limit of quantitation was 2.4 μg/100 g. The limits of detection and quantification of tocopherols ranged from 1.1 to 2.5 μg/100 g and 3.6 to 8.3 μg/100 g. The detection limit of ergocalciferol and cholecalciferol was 0.3 μg/100 g, and the limit of quantification was 1.0 μg/100 g. In the end, finished dishes such as dry fried hairtail, braised mushroom, steamed egg with soy sauce, sweet and sour ribs were repeatedly measured by this method for six times, and the relative standard deviation was less than 10%., Conclusion: The method has the characteristics of simple operation, good repeatability, high accuracy and friendly to operators and ecological environment. It can realize the simultaneous typing detection of vitamins A, D and E in finished dishes.

Background: Current clinical guidelines recommend surgery only for cT1-2N0M0 small cell lung cancer (SCLC) patients. In light of recent studies, the role of surgery in the treatment of SCLC needs to be reconsidered., Methods: We reviewed all SCLC patients who underwent surgery from November 2006 to April 2021. Clinicopathological characteristics were retrospectively collected from medical records. Survival analysis was performed by the Kaplan-Meier method. Independent prognostic factors were evaluated by Cox proportional hazard model., Results: 196 SCLC patients undergoing surgical resection were enrolled. The 5-year overall survival for the entire cohort was 49.0% (95% CI: 40.1-58.5%). PN0 patients had significantly superior survival to pN1-2 patients (p < 0.001). The 5-year survival rate of pN0 and pN1-2 patients were 65.5% (95% CI: 54.0-80.8%) and 35.1% (95% CI: 23.3-46.6%), respectively. Multivariate analysis revealed that smoking, older age, and advanced pathological T and N stages were independently associated with poor prognosis. Subgroup analyses demonstrated similar survival among pN0 SCLC patients regardless of pathological T stages (p = 0.416). Furthermore, multivariate analysis showed factors, including age, smoking history, type of surgery, and range of resection, were not independently prognostic factors for the pN0 SCLC patients., Conclusion: Pathological N0 stage SCLC patients have significantly superior survival to pN1-2 patients, regardless of features, including T stage. Thorough preoperative evaluation should be applied to estimate the status of lymph node involvement to achieve better selection of patients who might be candidate for surgery. Studies with larger cohort might help verify the benefit of surgery, especially for T3/4 patients., (© 2023. The Author(s).)

In this study, ultra-high performance liquid chromatography mass spectrometry (UPLC-MS) method was established for the characterization and quantitative determination of immunoglobulin G (IgG) subtypes (IgG1, IgG2, IgG3) in bovine dairy products. High-resolution mass spectrometry (HRMS) was applied to qualitatively confirm the theoretical peptides with specificity, enzymatic hydrolysis curve and stability among in heavy chain constant (CH1, CH2 and CH3) regions. The characteristic peptides VHNEGLPAPIVR, EPSVFIFPPKPK, GLPAPIVR, VVSALR were screened to quantitative analysis bovine IgG1, IgG2, IgG3 and the total amount of bovine IgG1 and IgG3, respectively. Isotope-labeled peptides were obtained by isotope dimethylation reaction, which aimed to correct the matrix effects. The results showed that the recovery was between 98.7% and 103.5%, and the precision of inter-day and intra-day was less than 6.8%. Moreover, this method had good linearity (R 2  ≥ 0.999). Therefore, this research provided an effective method for quantitatively detecting bovine IgG subtypes in milk and dairy products., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

An analytical method was established for the determination of trace α -amanitin in the urine of patients suffering from mushroom poisoning by online solid phase extraction-liquid chromatography-tandem mass spectrometry (online SPE-LC-MS/MS). The sample was protein precipitated with formic acid acidified acetonitrile-methanol (5:1, v/v). Reversed-phase liquid-liquid microextraction was used to remove the organic solvent from the sample extract. The toxin was purified by online SPE using an ODS micro column (5 mm×2.1 mm, 5 μm), and separated on an XBridge TM BEH C 18 column (150 mm×3.0 mm, 2.5 μm). Finally, the toxin was measured by MS/MS in the negative electrospray ionization (ESI - ) mode. Multiple reaction monitoring (MRM) was used, and the conditions were m/z 917.4>205.1 (quantitative ion transition) and m/z 917.4>257.1. Collision energy for both transitions was 55 eV. A fast valve-switching technique with a quantitative loop was used as an interface between the online SPE and LC-MS/MS modules. The two modules were independent, neither the mobile phase nor the pressure would interfere with each other, thus ensuring the stability of the system. Precise purification by the online system could effectively eliminate the matrix effects in the subsequent MS detection. Weak matrix suppression effects were found, with results of 88.7%-96.5%. The linear range of α -amanitin in urine was 0.1-50 μg/L with a correlation coefficient ( r 2 ) of 0.9983. The limit of detection (LOD) and limit of quantification (LOQ) in the sample matrix were 0.03 μg/L and 0.1 μg/L, respectively. The average recoveries at three spiked levels (0.1, 2.0 and 20 μg/L) were 84.3%-91.7% with relative standard deviations (RSDs) of 3.8%-7.2%. The accuracy and precision were evaluated using quality control samples with toxin contents of 0.1 μg/L (LOQ), 0.2 μg/L (2-fold LOQ), 2.0 μg/L (medium level), and 20 μg/L (high level). The calculated average intra-day accuracy was 85.1%-96.0% with the precision of 4.1%-7.8%. The inter-day accuracy was 82.9%-94.8% with the precision of 5.0%-9.5%. The specificity of the method was verified by negative samples derived from patients who suffered only gastroenteritis poisoning, without hepatotoxic symptoms. α -Amanitin was found in urine samples from nine mushroom poisoning patients with hepatotoxic symptoms. The sampling time ranged from 19 h to 92 h. The toxin contents were 0.11-53.1 μg/L. For patients with a high intake of poisonous mushrooms, the toxin content was 53.1 μg/L in a patient's urine sampled 19 h after accidental consumption and 0.19 μg/L in another patient's urine sampled 92 h after poisoning. The content of α -amanitin was only 0.53 μg/L in the urine sample obtained 23 h after consumption for a patient with low intake and 0.11 μg/L in the urine sampled from another patient 40 h after poisoning. Amatoxins can metabolize rapidly in vivo. The laboratory identification of amatoxin poisoning requires a method for trace-level analysis in the biological matrix. It is proved that this method is simple, accurate and sensitive by the application to the analysis of actual samples. The protein precipitation and reversed-phase liquid-liquid microextraction steps are fast and simple. Hence, they can be used as a rapid and effective pre-treatment method for online SPE-LC-MS/MS analysis of water-soluble toxins in biomaterial matrix. Highly sensitive analysis of α -amanitin in urine can be obtained using a precise purification technology via online SPE in this study. The problem of qualitative confirmation of the toxin at trace levels (0.03 μg/L) after poisoning can be solved. The laboratory identification time for amatoxin poisoning in some patients exceeds 90 h. The developed analytical method at trace level (0.1 μg/L of LOQ) can provide reliable technical support for establishing the dose-response relationship of α -amanitin in vivo. It can satisfy for the determination of trace α -amanitin in urine samples from patients with hepatotoxic mushroom poisoning.

Objective: Comparison and analysis of α-, β-, γ-, δ-tocopherol(T) and α-, β-, γ-, δ-tocotrienol(T3) in 44 species of seafood and aquatic products is under processed to enrich the database of food composition in China and provide a scientific reference for dietary intake choice., Methods: Quantitative and correlation analysis of eight vitamin E isomers were based on external calibration method with reversed-phase high-performance liquid chromatography-fluorescence detector, after hot saponification with alkaline and liquid-liquid extraction., Results: The content of α-tocopherol equivalent(α-TE) in seafood and aquatic products varied greatly(from 0. 10 to 4. 01 mg/100 g edible), as well as the isomer forms. Aspect of vitamin E forms in aquatic fish, detection rates of α-T and α-T3 were both 100%, while the rates of γ-T and γ-T3 were 31. 58% and 68. 42%, respectively. Aspect of vitamin E forms in sea fish, detection rates α-T3, γ-T and γ-T3 were 28. 57%, 28. 57% and 35. 71%, respectively, while the rate of α-T was 100%. The form of vitamin E isomers in fish was at some extent different when they raise up in wild and farming environment, whereas there was no significant different in content of isomers. For shrimp and crabs, the content of α-TE was also various(from 0. 31 to 14. 27 mg/100 g edible), whereas α-T was the primary vitamin E form. And the content of α-T in female crabs was a little higher than that in male crabs, without statistic difference. With respect to correlation analysis, there was a strong correlation between γ-T and α-T3 in sea fish, while weak correlation of isomers in aquatic fish and certain correlations of isomers in shrimp and crab., Conclusion: The level of vitamin E content in seafood and aquatic products are quite different. Thus, it will bring in different effects on total activity and intake of vitamin E isomers by consumption of different species of seafood and aquatic products.

Objective: To analyze the contents of fat-soluble vitamins in different kinds of eggs and egg products in Hangzhou City., Methods: The contents of fat-soluble vitamin A, vitamin E, vitamin K&#95;1 and vitamin K&#95;2(menaquinone-4, menaquinone-7 and menaquinone-9) in eggs and egg products were determined by the high-performance liquid chromatography method. The contents of vitamin D were determined by high performance liquid chromatography-tandem mass spectrometry. The determined contents were compared with the corresponding nutrient reference values., Results: The contents of vitamin A, vitamin D, vitamin E and vitamin K in different eggs and egg products were 64-278 μg RAE/100 g edible, 0. 2-9. 6 μg/100 g edible, 0. 59-2. 31 mg α-TE/100 g edible and 9. 5-84. 8 μg/100 g edible, respectively, accounting for 4%-192% of the corresponding nutrient reference values. The contents of fat-soluble vitamin A, vitamin D, vitamin E and vitamin K in duck, goose and quail eggs were higher than those in chicken eggs and pigeon eggs., Conclusion: There are some differences in fat-soluble vitamin A, vitamin D, vitamin E and vitamin K in different eggs and egg products, but there is no significant difference between groups.

Objective: To develop a method for simultaneous determination of 5 nitroimidazole antibiotics and 17 sulfonamides antibiotics in disinfection products by ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)., Methods: Samples were spiked with isotope internal standard, and then extracted by 2% formic acid solution and acetonitrile with ultrasonic, followed by MCX column to remove matrix interference and for enrichment. The supernatants were diluted with 2% formic acid solution before loading on the columns, then washed with 2% formic acid solution and methanol respectively, eluted with 5% ammonium methanol. The separation was performed on a CORTECS~(TM) UPLC C&#95;(18)(100 mm×2. 1 mm, 1. 6 μm) column by using 0. 1% formic acid solution and 0. 1% formic acid acetonitrile as mobile phase with gradient elution. The antibiotics were analyzed by UPLC-MS/MS., Results: The linear ranges of 22 antibiotics were 0. 05-5. 0 ng/mL and the correlation coefficients were greater than 0. 999. The limits of detection(LODs) were 0. 03-0. 15 μg/kg and the recoveries were 84. 3%-121. 2% with the relative standard deviations were 1. 13%-8. 43%(n=6). The method was successfully used to detect the content of antibiotics in 20 disinfection products, 45% of samples had been detected positively., Conclusion: This method is simple, sensitive, selective and accurate, and could be applied for simultaneous detection of antibiotics in disinfection products.

A fast and wide linear range method was established for the determination of mushroom toxins amanitins ( α -amanitin, β -amanitin and γ -amanitin) and phallotoxins (phallacidin and phalloidin) in wild mushrooms by online liquid chromatography-diode array detector-tandem mass spectrometry (LC-DAD-MS/MS). The mushroom toxins were extracted with methanol, and diluted with water. The extracts were separated on an XBridge TM BEH C 18 column (150 mm×3.0 mm, 2.5 μm) under pH 10.7, measured by DAD and then analyzed by MS/MS. Basic mobile phase conditions were applied to improve the ionization efficiency of hydrogen ion adducts. The baseline separation of the analytes was obtained within 15 min. The limits of detection (LODs) of the sample matrix were 0.005-0.02 mg/kg. The toxins were quantified by the results measured by MS/MS when the toxin contents less than 2 mg/kg, and quantified by the results obtained from DAD when the contents more than 2 mg/kg. The linear range was 0.05-500 mg/kg for the whole method in one injection. The method was successfully applied to the analyses of amanitins and phallotoxins in Lepiota brunneoincarnata and white Amanita .

A simultaneous determination method for ethyl carbamate (EC) and chloropropanols (3-monochloropropane-1, 2-diol (3-MCPD) and 2-monochloropropane-1, 3-diol (2-MCPD)) in flavorings was developed by gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS). After spiked with internal standard, the sample was extracted by matrix solid-phase dispersion extraction technique with an Extrelut NT column. Hexane was used to wash the fat soluble matrix interferences and then an ethyl acetate-ethyl ether (20: 80, v/v) mixture was added to elute the analytes. The concentrated extract was detected by GC-MS/MS in multiple reaction monitoring (MRM) mode. The limits of detection (LODs) were 2, 5 and 5 microg/kg for EC, 3-MCPD and 2-MCPD, respectively. The linear ranges were 5 - 1 000 microg/kg (r = 0.9997), 10-1000 microg/kg (r = 0.999 1) and 10-1000 microg/kg (r = 0.999 5) for EC, 3-MCPD and 2-MCPD, respectively. In soy sauce, yellow rice wine, salami sauce and flavoring of instant noodle matrices, the recoveries (RSDs, n = 7) in MRM mode at the levels of 20, 100 and 400 microg/kg were 87.7%-104% (4.3%-10.7%), 90.1%-109% (2.6%-10.2%), and 90.9%-103% (3.0%-9.5%), respectively. EC, 3-MCPD and 2-MCPD were found in some real samples of the soy sauce, wine and flavoring of instant noodle. EC or 3-MCPD was found in some of the salami samples. The method is accurate, fast and suitable for the simultaneous determination of EC, 3-MCPD and 2-MCPD in flavorings.

A series of NCO/NCS pincer precursors, 3-(Ar(2)OCH2)-2-Br-(Ar(1)N=CH)C6H3 (((Ar1)NCO(Ar2))Br, 3a-d) and 3-(2,6-Me2C6H3SCH2)-2-Br-(Ar(1)N=CH)C6H3 (((Ar1)NCS(Me))Br, 4a and 4b) were synthesized and characterized. The reactions of [(Ar1)NCO(Ar2)]Br/[(Ar1)NCS(Me)]Br with nBuLi and the subsequent addition of the rare-earth-metal chlorides afforded their corresponding rare-earth-metal-pincer complexes, that is, [((Ar1)NCO(Ar2))YCl2(thf)2] (5a-d), [((Ar1)NCO(Ar2))LuCl2(thf)2] (6a, 6d), [((Ar1)NCO(Ar2))GdCl2(thf)2] (7), [{((Ar1)NCS(Me))Y(μ-Cl)}2{(μ-Cl)Li(thf)2(μ-Cl)}2] (8, 9), and [{((Ar1)NCS(Me))Gd(μ-Cl)}2{(μ-Cl)Li(thf)2(μ-Cl)}2] (10, 11). These diamagnetic complexes were characterized by (1)H and (13)C NMR spectroscopy and the molecular structures of compounds 5a, 6a, 7, and 10 were well-established by X-ray diffraction analysis. In compounds 5a, 6a, and 7, all of the metal centers adopted distorted pentagonal bipyramidal geometries with the NCO donors and two oxygen atoms from the coordinated THF molecules in equatorial positions and the two chlorine atoms in apical positions. Complex 10 is a dimer in which the two equal moieties are linked by two chlorine atoms and two Cl-Li-Cl bridges. In each part, the gadolinium atom adopts a distorted pentagonal bipyramidal geometry. Activated with alkylaluminum and borate, the gadolinium and yttrium complexes showed various activities towards the polymerization of isoprene, thereby affording highly cis-1,4-selective polyisoprene, whilst the NCO-lutetium complexes were inert under the same conditions., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)