Foods
·
2022
·Vol. 12
·期 1
·138
·
IF 5.561
Min Li,Pengxiang Wang,Xu Zhang,Hongyu Wang,Ke Li,Yanhong Bai
Heterocyclic aromatic amines (HAAs) generated during the cooking of meats cause adverse effects on human health. The purpose of the current research was to develop a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) method using magnetic multi-walled carbon nanotubes (Fe3O4-MWCNTs) as clean-up adsorbents for the rapid determination of HAAs in braised sauce beef. The significant parameters in extraction and clean-up processes were screened and optimized. Under optimal conditions, the LODs ranged from 3.0 ng/g to 4.2 ng/g. The recoveries (78.5–103.2%) and relative standard deviations RSDs (<4.6%) of five HAAs were obtained. These are in accordance with the validation criteria (recovery in the range of 70–120% with RSD less than 20%). Compared with conventional clean-up adsorbents (PSA or C18), Fe3O4-MWCNTs displayed equivalent or better matrix removal efficiency, while making the pretreatment process easier and more time-saving through magnetic separation. Less usage of adsorbent makes the method possess another advantage of being lower in cost per sample. The method developed was successfully applied to analyze real samples collected from local deli counters, demonstrating Fe3O4-MWCNTs could be considered as an effective alternative adsorbent with great potential in the QuEChERS process.Keywords:heterocyclic aromatic amines;QuEChERS;Fe3O4-MWCNTs;braised sauce beef
研究领域:
食品科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Flow Chemistry
·
2018
·Vol. 8
·期 3
·139-146
·
IF 1.658
Liu Yang,Zeng Changfeng,Wang Chongqing,Zhang Lixiong
We design a new continuous diazotization microreaction process in which concentrated acid and sodium nitrite solutions are used. We form oil in water (O/W) microdroplets by mixing amine with sodium nitrite aqueous solution, which react with mineral acid to make the diazotization. In this way, the formed particles are dispersed in the aqueous phase, which can flow with the main stream, and consequently are consumed. Then the fluid can smoothly flow without clogging in the microchannels and we can achieve continuous operation. We use aniline, o-methylaniline, m-methylaniline, and o-ethylaniline as the raw materials, 6 M HCl and 6.5 M H 2 SO 4 as the acid as well as sodium nitrite to demonstrate the feasibility. The resulting diazonium salts are converted to iodo-substitute aromatic compounds to measure the yield. The results show that, SIMM-V2 micromixer is efficient to form the emulsion. Mixing the microdroplets with acid in a co-axial flow way can prevent clogging. In hydrochloric acid medium, high reaction yield can be obtained when the reaction temperature is 4 °C and the residence time is 13–15 s. In sulfuric acid medium, high conversion of aromatic amine of up to 99% and yield of approximately 90% can be achieved at the reaction temperature of 9 °C and the residence time of 14–16 s. This process provides efficient continuous diazotization reactions using concentrated acid and sodium nitrite solutions, minimizing the production of waste water.
研究领域:
化学工程
·
有机合成
✓ 已验证
DOI
高影响因子
Canadian Journal of Chemistry
·
2011
·Vol. 89
·期 6
·
IF 1.374
ZhuYefeng,WeiYunyang
The copper(I) iodide/1,4-bis(2-hydroxy-3,5-di-tert-butylbenzyl)piperazine (CuI–L2) system catalyzed the cross-coupling reactions between aryl halides and aqueous ammonia in water to produce primary aromatic amines in good yields. The protocol was simple and efficient, avoiding the need for inert atmosphere, additional base, or other additives.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
PNAS Nexus
·
2024
·Vol. 3
·期 2
·
IF 2.2
Wu Jing-Hang,Yang Tian-Hao,Chen Fei,Yu Han-Qing
Aromatic amines (AAs), ubiquitous in industrial applications, pose significant environmental hazards due to their resistance to conventional wastewater treatments. Peracetic acid (PAA)-based advanced oxidation processes (AOPs) have been proposed as effective strategies for addressing persistent AA contaminants. While the organic radicals generated in these systems are believed to be selective and highly oxidative, acetate residue complicates the evaluation of AA removal efficiency. In this work, we explored transformation pathways of AAs in a representative Co(II)-catalyzed PAA system, revealing five side reactions (i.e. nitrosation, nitration, coupling, dimerization, and acetylation) that yield 17 predominantly stable and toxic by-products. The dominant reactive species was demonstrated as Co–OOC(O)CH3, which hardly facilitated ring-opening reactions. Our findings highlight the potential risks associated with PAA-based AOPs for AA degradation and provide insights into selecting suitable catalytic systems aimed at efficient and by-product-free degradation of pollutants containing aromatic –NH2.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2025
·
IF 4.6
Longwei Jiang,Iftikhar Hussain Badar,Ziwen Yang,Guanhua Li,Yingying Hu,Lang Zhang
This study examined how varying roasting times influenced the formation of free and bound heterocyclic aromatic amines (HAAs) in beef during the roasting process. The findings showed that as the roasting time increased, the water content and color decreased ( P < 0.05), whereas glucose, creatine, and creatinine levels increased ( P < 0.05) from 0.05 to 2.45, 2.68–4.96, and 0.07–0.91 mg/g, respectively. A total of 7 free HAAs (IQx, MeIQx, MeIQ, PhIP, 4,8-DiMeIQx, Harman, and Norharman) and 5 bound HAAs (MeIQx, AαC, 7,8-DiMeIQx, Harman, and Norharman) were detected in the roasted beef by high performance liquid chromatography-mass spectrometry (HPLC-MS/MS). The bound HAA content in the roasted beef was significantly higher than that of the free HAAs. As the roasting time increased, the bound HAAs increased from 2125.08 to 2326.45 ng/g, while the free HAAs increased from 45.72 to 121.38 ng/g ( P < 0.05). Correlation analysis revealed that the development of free and bound HAAs was positively associated with glucose, creatine, and creatinine, and the FAAs were positively correlated with the formation of MeIQx through partial least squares regression (PLSR) analysis. These findings would help minimize the development of free and bound HAAs in roasted meat products.
研究领域:
食品科学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2013
·
IF 2.915
Y.-W. Sun,X.-H. Lu,X.-L. Wei,D. Zhou,Q.-H. Xia
Co 2+ -exchanged zeolite catalysts were prepared by an ion-exchange route and firstly applied in the N -alkylation of aromatic amines with alcohols to imines. For the N -alkylation of aniline with benzyl alcohol, the aniline conversion of 89.8 mol% with an imine selectivity of 100% was achieved over Co-13X at 433 K under optimal conditions. The results showed that many factors including the Co loading, the support, the temperature, the alkali, could influence the reactions. Investigations carried out by XRD, SEM and recycling studies indicated that the Co-13X catalyst still remained porous structures of 13X zeolite and possessed a stable catalytic activity.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2021
·Vol. 45
·期 4
·929-937
·
IF 3.645
Xiaoyan Ouyang,Yuling Hu,Gongke Li
In this work, an integrated sample-pretreatment strategy for the separation and enrichment of microplastics and primary aromatic amines from the migration of teabag was developed. The migration solution of teabag was passed through a homemade device. The microplastics were firstly captured by a silver membrane, and then the primary aromatic amines were enriched by a solid-phase extraction column. The microplastics migrated from teabag were detected by attenuated total reflection-Fourier transform infrared spectrometer and Raman spectroscopy. The data showed the character, the number of particles, area ratio, and morphology of microplastics migrated from the teabag. Subsequently, after the enrichment procedure, a sensitive analytical method for primary aromatic amines was established followed by ultra-high performance liquid chromatography-tandem mass spectrometry. The method showed wide linear ranges with R 2 greater than 0.9915, low limits of detection (2–18 ng/L), and low limits of quantification (8–50 ng/L). The developed method was adopted to analyze microplastics and primary aromatic amines migrated from nylon and polyethylene terephthalate teabag under different temperatures and times. The integrated sample-pretreatment strategy displayed promising potentials in the one-step preparation of the microplastics and hazardous molecules in the sample of environment and food security.
研究领域:
环境科学
·
食品安全
·
分析化学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2019
·
IF 3.774
Yunwu Zheng,Zhen Wang,Can Liu,Lei Tao,Yuanbo Huang,Zhifeng Zheng
By introducing exogenous nitrogen during biomass pyrolysis under nitrogen-rich conditions, high-value nitrogen-containing products, i.e., nitrogen-rich char and oil may be produced. Based on the cogeneration of high-value nitrogen products from biomass, biomass nitrogen-enriched pyrolysis was performed in a fixed bed with different sources and contents of ammonia. The yields, composition and characteristics of the products were investigated. Moreover, the formation mechanism of N-containing species was explored in depth for the pyrolysis and catalytic pyrolysis with HZSM-5 and Zn/HZSM-5 catalysts via elemental analysis, XPS, FTIR and BET. The results showed that ammonia impregnation could promote a Maillard reaction, reduce the content of small aldehydes and ketones, and produce a nitrogen-enriched bio-oil. The contents of N-containing species and phenolic substances in the pyrolysis oil of biomass impregnated with 10% urea reached 15.66% and 56.69%, respectively. Moreover, the nitrogen on the coke surface after pretreatment was mainly composed of C N, C N and N COO functional groups. The bio-char generated abundant pyridinic-N, pyrrolic-N, quaternary-N, and pyridone-N oxides. The presence of urea introduced many alkaline N-containing functional groups on the surface of the bio-char and promoted the transformation of nitrogen from amides and imides to heterocyclic nitrogen with higher thermal stability. Furthermore, Zn was an excellent catalyst for the Maillard reaction, and the Zn/HZSM-5 catalyst had a higher selectivity for aromatic hydrocarbons (96.98% for biomass and 86.48% for urea/biomass) and N-containing heterocyclic compounds, such as indoles (6.16% for biomass and 13.51% for urea/biomass). Additionally, the coke content decreased, and the catalyst deactivation decreased.
研究领域:
能源与环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2022
·Vol. 307
·期 12
·2200351
·
IF 4.402
Haolan Gou,Ying Bao,Jiateng Huang,Xiaoma Fei,Xiaojie Li,Wei Wei
Heat-resistant
molding of compounds is an indispensable part in encapsulating future electronic power devices. Herein, it is used for polyfunctional epoxy resin (EP) and diamine-phenol benzoxazine (BOZ) as resin matrix, 4,4'-diaminodiphenylmethane (DDM) as curing agent, and iron acetylacetonate (Fe(acac) 3 ) as curing accelerator, as well as inorganic fillers and other auxiliaries, to prepare heat-resistant molding compounds. The curing behavior, processability and thermal performance of the EP/DDM/BOZ (EDB) resin blends containing different contents of DDM, BOZ, and Fe(acac) 3 are first systematically investigated. The EDB molding compounds (MC EDB ) with suitable BOZ content show good processability, and the molding process can be compatible with that of commercial epoxy molding compounds (EMC). With increasing the BOZ content, the glass transition temperature of cured MC EDB is greatly enhanced to a maximum of 261 °C determined by dynamic mechanical analyzer, owing to the hydrogen-bond interaction generated after polymerization of BOZ increasing the rigidity of network chains. Moreover, the cured MC EDB also exhibits higher thermal decomposition stability, better high-temperature (200 °C) mechanical properties, and lower water absorption compared to the cured EMC. After high-temperature (200 °C) aging for 500 h, the cured MC EDB with suitable BOZ content still maintains outstanding performance. This study provides a promising strategy for preparing heat-resistant electronic packaging molding compounds.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2022
·
IF 4.198
Menghan Cui,Rong Wang,Qing Yang,Chunxiang Kuang
Herein, we report the copper-catalyzed one-pot Sandmeyer-type reaction of aromatic amines with triazoles to afford N-aryl-1,2,3-triazoles. Diazonium salts, formed from aromatic amines and tert-butyl nitrite in the presence of fluoroboric acid, reacted with triazoles in a copper-catalyzed Sandmeyer-type reaction. The reaction proceeded under mild conditions to afford N-aryltriazoles in moderate to good yields. This method is amenable to a wide range of aromatic amines and triazoles and shows diverse functional group tolerance. Inhibition of the reaction upon the addition of free radical scavengers suggested a radical pathway, in which the aryl radical, copper, and triazole formed a complex that underwent reductive elimination to give aryltriazole compounds; this is consistent with the mechanism underlying the Sandmeyer reaction. Thus, we demonstrate a new effective strategy for the construction of C–N bonds via Sandmeyer-type reactions and a valuable alternative approach for the synthesis of aryltriazole derivatives.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2011
·
IF 2.635
Haiyan Li,Zhongduo Xiong,Xibin Dai,Qinqfu Zeng
In order to investigate the impact of perspiration on photo-induced chemical reaction of azo dyes and the carcinogenic aromatic amine products produced from the reaction, we have carried out experimental studies on the photochemical reaction of C.I. Reactive Red 2 mixed with American Association of Textile Chemists and Colorists（AATCC）standard artificial perspiration. UV–vis spectroscopic technique was employed to monitor the reaction processes, and the reaction products were analyzed by hollow fiber protected liquid-liquid-liquid phase micro-extraction with capillary electrophoresis（HF-LLLME-CE). The results showed that perspiration had remarkable influence on the photochemical reaction of azo dyes. Aromtic amines formed during the photochemical process as a result of reduction of azo dyes by organic components in perspiration. The HF-LLLME-CE methodology was validated in analyzing aromatic amines produced from the photochemical degradation of azo dye C.I. Reactive Red 2 and C.I. Acid Red 35 mixed with artificial perspiration.
研究领域:
分析化学
·
毒理学
·
环境科学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Tianxing Wang,Wei Liu,Ling Chen,Xiaoxi Li
Foodborne heterocyclic aromatic amines (HAAs) are potent mutagens and carcinogens, posing significant health risks. Existing enrichment methods for HAAs need better adsorption selectivity and capacity for daily exposure assessment. This study hypothesized that introducing carboxylic groups into magnetic covalent organic frameworks (m-COFs) would improve HAAs adsorption by providing additional binding sites. Hence, we prepared a novel magnetic adsorbent, termed as Fe 3 O 4 @DOPA-TpPa-(COOH) 2 capable of enhancing the HAAs detection through magnetic solid-phase extraction (MSPE) coupled with UPLC-MS. This sorbent demonstrated a large specific surface area (130.7 m 2 /g), high magnetic responsivity (21.05 emu/g), and robust stability, with an adsorption capacity (Qm[cal]: 81.82 mg/g) driven by electrostatic, LP − π/C-H − π interactions, and hydrogen bonding. Optimal MSPE conditions provided sensitive detection with a broad linear range (5–500 ng/mL), low limits of detection (0.01–7.01 ng/g), and excellent repeatability. Application to Cantonese mooncake samples showed satisfactory recoveries (62.12%–126.86%). This method offers a more accurate tool for detecting HAAs.
研究领域:
食品安全
·
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）