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In this work, a novel fluorinated magnetic microporous organic network (Fe3O4@FMON) was exquisitely designed and synthesized for highly efficient and selective magnetic solid phase extraction (MSPE) of fluorinated benzoylurea insecticides (BUs) from complex tea beverage samples. The Fe3O4@FMON exhibited good extraction for BUs via the pre-designed hydrophobic, π-π stacking, hydrogen bonding and specific FF interactions. A sensitive Fe3O4@FMON-based MSPE-HPLC-UV method with wide linear range (0.10-1000 µg L-1, R2 ≥ 0.996), low limits of detection (0.01-0.02 µg L-1), and large enrichment factors (85.6-98.0) for BUs from tea beverage samples was developed. By decorating F elements within MON's networks, the Fe3O4@FMON characterized good hydrophobicity and chemical stability, which could be reused at least 8 times without decrease of recoveries. This work demonstrated the great prospects of Fe3O4@FMON for enriching trace BUs from complex substrates and triggered the potential of FMON for sample pretreatment of fluorinated analytes.
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The overuse of nonsteroidal anti-inflammatory drugs (NSAIDs) poses many serious environmental and food safety concerns. Development of effective and sensitive sample pretreatment method for monitoring trace NSAIDs from complex samples is of great significance. Depending on the ionic and aromatic structures of NSAIDs, a cationic microporous organic network (MON) named TEPM-BBDC with large specific surface area, good solvent and thermal stabilities, and numerous interaction sites was designed and prepared for efficient solid-phase extraction (SPE) of four typical NSAIDs (flurbiprofen, ketoprofen, naproxen, and diclofenac sodium) from environmental water and milk samples. By anchoring the ionic groups in the conjugated MON frameworks, the prepared TEPM-BBDC offered good extraction for NSAIDs based on the π-π, hydrophobic, ion exchange, and electrostatic interactions. Under the optimal extraction conditions (initial concentration of each NSAID: 200 g L-1; sample volume: 50 mL; desorption solvent: 1.5 mL of MeOH + 1 % NH3·H2O; sample loading rate: 5 mL min-1; NaCl concentration: 0 mmol L-1; pH = 5), the proposed TEPM-BBDC-SPE-HPLC-UV method owned wide linear range (0.50-1000 g L-1), low limits of detection (0.10-0.40 g L-1), large enrichment factors (92.2-99.2), good precisions (intra-day and inter-day, RSD% = 1.3-7.8 %, n = 6) and reproducibility (column-to-column, RSD% = 8.0 %, n = 3). The developed method also exhibited good recoveries (83.6-113.4 %) for the determination of NSAIDs in river water, lake water and milk samples. This work not only revealed the potential of TEPM-BBDC for SPE of ionic NSAIDs in complex samples, but also highlighted the prospect of ionic MONs in sample pretreatment.
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Anti-Inflamatórios não Esteroides , Limite de Detecção , Leite , Extração em Fase Sólida , Poluentes Químicos da Água , Extração em Fase Sólida/métodos , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/isolamento & purificação , Leite/química , Animais , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Cromatografia Líquida de Alta Pressão/métodos , Porosidade , Cátions/química , Reprodutibilidade dos Testes , AdsorçãoRESUMO
Cembranolides are characteristic metabolites in marine soft corals, with complex structures and widespread biological activities. However, seldom has an intensive pharmacological study been done for these intriguing marine natural products. In this work, systematic chemical investigation was performed on Sinularia pedunculata by HSQC-based small molecule accurate recognition technology (SMART), resulting in the isolation and identification of 31 cembrane-type diterpenoids, including six new ones. In the bioassay, several compounds showed significant anti-inflammatory activities on the inhibition of NO production. The structure-activity relationship (SAR) was comprehensively analyzed, and two most bioactive and less toxic compounds 8 and 9 could inhibit inflammation through suppressing NF-κB and MAPK signaling pathways, and reduce the secretion of inflammatory cytokines. In a mouse model of dextran sodium sulfate (DSS)-induced acute colitis, 8 and 9 exhibited good anti-inflammatory effects and the ability to repair the colon epithelium, giving insight into the application of cembranolides as potential ulcerative colitis (UC) agents.
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Antozoários , Colite Ulcerativa , Sulfato de Dextrana , Diterpenos , Animais , Colite Ulcerativa/tratamento farmacológico , Diterpenos/farmacologia , Diterpenos/química , Diterpenos/uso terapêutico , Diterpenos/isolamento & purificação , Camundongos , Relação Estrutura-Atividade , Antozoários/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/isolamento & purificação , Células RAW 264.7 , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Descoberta de Drogas , Camundongos Endogâmicos C57BL , Humanos , Masculino , Óxido Nítrico/metabolismoRESUMO
In this work, a novel polyaniline-modified magnetic microporous organic network (MMON-PANI) composite was fabricated for effective magnetic solid phase extraction (MSPE) of five typical nonsteroidal anti-inflammatory drugs (NSAIDs) from animal-derived food samples before high performance liquid chromatography (HPLC) detection. The core-shell sea urchin shaped MMON-PANI integrates the merits of Fe3O4, MON, and PANI, exhibiting large specific surface area, rapid magnetic responsiveness, good stability, and multiple binding sites to NSAIDs. Convenient and effective extraction of trace NSAIDs from chicken, beef and pork samples is realized on MMON-PANI via the synergetic π-π, hydrogen bonding, hydrophobic, and electrostatic interactions. Under optimal conditions, the MMON-PANI-MSPE-HPLC-UV method exhibits wide linear ranges (0.2-1000 µg L-1), low limits of detection (0.07-1.7 µg L-1), good precisions (intraday and inter-day RSDs < 5.4 %, n = 3), large enrichment factors (98.6-99.9), and less adsorbent consumption (3 mg). The extraction mechanism and selectivity of MMON-PANI are also evaluated in detail. This work proves the incorporation of PANI onto MMON is an efficient way to promote NSAIDs enrichment and provides a new strategy to synthesize multifunctional MON-based composites in sample pretreatment.
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Compostos de Anilina , Anti-Inflamatórios não Esteroides , Extração em Fase Sólida , Compostos de Anilina/química , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/química , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Suínos , Galinhas , Bovinos , Adsorção , Carne/análise , Porosidade , Reprodutibilidade dos TestesRESUMO
Owing to their incomplete digestion in the human body and inadequate removal by sewage treatment plants, antiepileptic drugs (AEDs) accumulate in water bodies, potentially affecting the exposed humans and aquatic organisms. Therefore, sensitive and reliable detection methods must be urgently developed for monitoring trace AEDs in environmental water samples. Herein, a novel phenylboronic acid-functionalized magnetic cyclodextrin microporous organic network (Fe3O4@CD-MON-PBA) was designed and synthesized via the thiol-yne click post-modification strategy for selective and efficient magnetic solid-phase extraction (MSPE) of trace AEDs from complex sample matrices through the specific B-N coordination, π-π, hydrogen bonding, electrostatic, and host-guest interactions. Fe3O4@CD-MON-PBA exhibited a large surface area (118.5 m2 g-1), rapid magnetic responsiveness (38.6 emu g-1, 15 s), good stability and reusability (at least 8 times), and abundant binding sites for AEDs. Under optimal extraction conditions, the proposed Fe3O4@CD-MON-PBA-MSPE-HPLC-UV method exhibited a wide linear range (0.5-1000 µg L-1), low limits of detection (0.1-0.5 µg L-1) and quantitation (0.3-2 µg L-1), good anti-interference ability, and large enrichment factors (92.2-104.3 to 92.3-98.0) for four typical AEDs. This work confirmed the feasibility of the thiol-yne click post-synthesis strategy for constructing novel and efficient multifunctional magnetic CD-MONs for sample pretreatment and elucidated the significance of B-N coordination between PBA and N-containing AEDs.
Assuntos
Anticonvulsivantes , Ácidos Borônicos , Química Click , Ciclodextrinas , Extração em Fase Sólida , Compostos de Sulfidrila , Ácidos Borônicos/química , Anticonvulsivantes/química , Anticonvulsivantes/isolamento & purificação , Anticonvulsivantes/síntese química , Extração em Fase Sólida/métodos , Ciclodextrinas/química , Porosidade , Compostos de Sulfidrila/química , Alcinos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Limite de DetecçãoRESUMO
The abnormal estrogens levels in human body can cause many side effects and diseases, but the quantitative detection of the trace estrogens in complex biological samples still remains great challenge. Here we reported the fabrication of a novel core-shell structured magnetic cyclodextrin microporous organic network (Fe3O4@CD-MON) for rapid magnetic solid phase extraction (MSPE) of four estrogens in human serum and urine samples prior to HPLC-UV determination. The uniform spherical core-shell Fe3O4@CD-MONs was successfully regulated by altering the reactive monomers and solvents. The Fe3O4@CD-MONs owned high specific surface area, good hydrophobicity, large superparamagnetism, and abundant extraction sites for estrogens. Under optimal conditions, the proposed MSPE-HPLC-UV method provided wide linearity range (2.0-400 µg L-1), low limits of detection (0.5-1.0 µg L-1), large enrichment factors (183-198), less adsorbent consumption (3 mg), short extraction time (3 min), and good stability and reusability (at least 8 cycles). The established method had also been successfully applied to the enrichment and detection of four estrogens in serum and urine samples with a recovery of 88.4-105.1 % and a relative standard deviation of 1.0-5.9 %. This work confirmed the feasibility of solvent and monomer regulation synthesis of Fe3O4@CD-MON composites, and revealed the great prospects of magnetic CD-MONs for efficient enrichment of trace estrogens in complex biological samples.
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Estrogênios , Limite de Detecção , Extração em Fase Sólida , beta-Ciclodextrinas , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Estrogênios/urina , Estrogênios/sangue , Estrogênios/isolamento & purificação , Estrogênios/análise , Estrogênios/química , Extração em Fase Sólida/métodos , beta-Ciclodextrinas/química , Solventes/química , Porosidade , Nanopartículas de Magnetita/química , AdsorçãoRESUMO
The highly conjugated and hydrophobic characteristics of microporous organic networks (MONs) have largely impeded their broad applications in sample pretreatment especially for the polar or ionic analytes. In this work, a novel uniform hollow shaped sulfonate group functionalized MON (H-MON-SO3H-2) was synthesized via the sacrificial template method for the efficient solid phase extraction (SPE) of sulfonamides (SAs) from environmental water, milk, and honey samples prior to HPLC analysis. H-MON-SO3H-2 exhibited large specific surface area, penetrable space, good stability, and numerous hydrogen bonding, electrostatic, hydrophobic and π-π interaction sites, allowing sensitive SPE of SAs with wide linear range (0.150-1000 µg L-1), low limit of detection (0.045-0.188 µg L-1), good precisions (intra-day and inter-day RSD < 7.3%, n = 5), large enrichment factors (95.7-98.5), high adsorption capacities (250.4-545.0 mg g-1), and satisfactory reusability (more than 80 times). Moreover, the established method was successfully applied to extract SAs from spiked samples with the recoveries of 86.1-104.3%. This work demonstrated the great potential of H-MON-SO3H-2 in the efficient SPE of trace SAs in complex environmental water and food samples and revealed the prospect of hollow MONs in sample pretreatment.
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Antibacterianos , Mel , Antibacterianos/análise , Mel/análise , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Sulfanilamida/análise , Água/química , Sulfonamidas/análiseRESUMO
Cephalosporins (CEFs) are a class of widely used toxic antibiotics. Development of a rapid and sensitive method for detecting trace CEF residues in food samples is still challenging. Herein, we report preparation of an amide and carboxyl groups dual-functionalized core-shelled magnetic microporous organic network MMON-COOH-2CONH for efficient magnetic solid-phase extraction (MSPE) of CEFs from milk powder samples. Under optimal conditions, the established MMON-COOH-2CONH-MSPE-HPLC-UV method owns wide linear range (3-10000 µg kg-1), low limits of detection (1-3 µg kg-1), large enrichment factors (93.9-99.4), low adsorbent consumption (3 mg), and short extraction time (6 min). Synergistic extraction mechanisms of ionic bonding, hydrogen bonding, π-π, and hydrophobic interactions were elucidated by both theoretical density functional theory calculations and experimental data. This study confirms that preparation of dual-functionalized MMONs and introduction of ionic groups are feasible to promote MMONs application in sample pretreatment.
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Amidas , Cefalosporinas , Magnetismo , Fenômenos Físicos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Fenômenos Magnéticos , Limite de DetecçãoRESUMO
Endocrine disrupting chemicals (EDCs) are a typical class of natural or man-made endogenous hormone agonists or antagonists that can directly or potentially interfere with human endocrine system. However, it is still difficult to analyze trace EDCs directly from complex environment and food matrices. Therefore, the proper sample pretreatment is highly desired and the preparation of efficient adsorbents is of great challenge and importance. Herein, we report the facile one-pot solvothermal synthesis of Fe3O4 nanoparticle doped magnetic ß-cyclodextrin microporous organic network composites (MCD-MONs) for the magnetic solid phase extraction (MSPE) of four phenolic EDCs in water and food takeaway boxes prior to the high-performance liquid chromatography analysis. The sheet-like Fe3O4 doped MCD-MONs offered good magnetic property (16.5 emu g-1) and stability, and provided numerous hydrogen bonding, hydrophobic, π-π, and host-guest interaction sites for EDCs. Under the optimal experimental conditions, the established method was successfully verified with wide linear range (2.0-1000 µg L-1), low limits of detection (0.6-1.0 µg L-1), good precisions (intra-day and inter-day RSDs < 5.2 %, n = 3), large enrichment factors (88-98) and adsorption capacity (90.3-255.8 mg g-1), short extraction time (6 min), less adsorbent consumption (3 mg), and good reusability (at least 8 times) for EDCs. The proposed method was successfully applied to detect the trace EDCs in real samples with the recovery of 84.0-99.7 %. This work demonstrated the great potential of MCD-MONs for the efficient MSPE of trace EDCs from complex food takeaway boxes and water samples and uncovered the prospect of CD-based MONs in sample pretreatment.
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Disruptores Endócrinos , beta-Ciclodextrinas , Humanos , Disruptores Endócrinos/análise , Água/química , Magnetismo/métodos , Cromatografia Líquida de Alta Pressão , Fenômenos Magnéticos , beta-Ciclodextrinas/química , Extração em Fase Sólida/métodos , Limite de DetecçãoRESUMO
Despite the rapid development of versatile metal-organic frameworks (MOFs), the synthesis of water-stable MOFs remains challenging, which significantly limits their practical applications. Herein, a novel engineering strategy was developed to prepare superhydrophobic MOFs by an in situ fluorinated microporous organic network (FMON) coating. Through controllable modification, the resulting MOF@FMON retained the porosity and crystallinity of the pristine MOFs. Owing to the superhydrophobicity of the FMON and the feasibility of MOF synthesis, the FMON coating could be in situ integrated with various water-sensitive MOFs to provide superhydrophobicity. The coating thickness and hydrophobicity of the MOF@FMON composites were easily regulated by changing the FMON monomer concentration. The MOF@FMON composites exhibited excellent oil/water separation and catalytic activities and enhanced durability in aqueous solutions. This study provides a general approach for the synthesis of superhydrophobic MOFs, expanding the application scope of MOFs.
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A zwitterionic magnetic microporous organic network (MMON-SO3H-NH2) with numerous amino and sulfonic acid ion-pare binding sites was designed and synthesized for efficient magnetic solid-phase extraction (MSPE) of fluoroquinolones (FQs) from meat samples. The core-shell MMON-SO3H-NH2 offered large specific surface area, rapid magnetic responsiveness, good stability, and multiple binding sites for FQs. The density functional theory and independent gradient model evaluations confirmed hydrogen bonding, π-π and ion-pair interactions between MMON-SO3H-NH2 and FQs. Under the optimal conditions, the established MMON-SO3H-NH2-MSPE-HPLC-UV method gave wide linear range (0.15-1000 µg L-1), low limits of detection (0.05-4.5 µg L-1) and limits of quantitation (0.15-13 µg L-1), and high enrichment factors (82.1-99.6) using 3 mg of adsorbent. This work demonstrates that the preparation of zwitterionic MONs is an efficient way to promote the extraction performance of MONs for zwitterionic targets and provides an effective sample pretreatment method for enriching and monitoring FQs in complex food matrices.
Assuntos
Fluoroquinolonas , Extração em Fase Sólida , Fluoroquinolonas/análise , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida/métodos , Antibacterianos , Carne/análise , Fenômenos Magnéticos , Limite de DetecçãoRESUMO
OBJECTIVE: To translate the career success in nursing scale (CSNS) into Chinese and evaluate its psychometric properties. BACKGROUND: A lower sense of career success seriously affects the enthusiasm of nurses and increases their turnover rate. Therefore, an accurate assessment of the career success level of nurses is necessary. However, China does not have a professional tool for assessing the career success of nurses. METHODS: The stratified sampling method was used to recruit participants from 22 hospitals of different grades in 5 cities in China. A total of 650 and 348 subjects were selected for item analysis and reliability and validity tests, respectively, of the translated initial scale. RESULTS: The Chinese version of the CSNS (C-CSNS) with 33 items had good psychometric properties. Cronbach's α was 0.960, split-half reliability was 0.893, and ICC within two weeks was 0.981. Exploratory factor analysis extracted 5 common factors that explained 63.73% of the total variance, and confirmatory factor analysis supported acceptable construct validity. CONCLUSION: The C-CSNS has adequate construct validity and excellent psychometric properties and can be used for accurate assessment of nurses' career success. IMPLICATIONS FOR NURSING MANAGEMENT: A new tool that is more suitable for the Chinese hospital nursing context is available for evaluating Chinese clinical nurses' career success. Nursing managers can formulate appropriate management strategies according to the evaluation results to assist nurses in career development planning, thereby improving their career success level.
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PURPOSE: Radiotherapy can negatively affect the pelvic floor function of patients with cervical cancer; however, the impact of different radiotherapy times and other related factors on pelvic floor function in cervical cancer survivors during radiotherapy remains unclear. We aimed to investigate the status of pelvic floor dysfunction (PFD) in cervical cancer survivors during radiotherapy and to analyze the factors influencing PFD. METHODS: In this cross-sectional study, a convenience sampling method was used to recruit cervical cancer survivors undergoing radiotherapy from January 2022 to July 2022 at a tertiary first-class hospital located in northeastern China. The Pelvic Floor Distress Inventory-Short Form 20 was used for participants' self-report of their PFD during radiotherapy. RESULTS: Data from 120 cervical cancer survivors were included in this study. The results showed that the mean PFDI-20 total score was 32.69 ± 7.76. Multiple stepwise linear regression analysis showed that 56.9% of the variance in PFD was explained by age (ß = 0.25, p < 0.001), body mass index (ß = 0.32, p < 0.001), recurrence (ß = 0.29, p < 0.001), number of radiotherapy sessions (ß = 0.39, p < 0.001), and number of deliveries (ß = 0.35, p < 0.001). CONCLUSION: It is important to pay more attention to the PFD status of cervical cancer survivors receiving radiotherapy. Future therapeutic approaches should involve early identification of relevant risk factors early to provide patients with personalized care at different stages of radiotherapy for reducing their discomfort and improving their health-related quality of life.
Assuntos
Sobreviventes de Câncer , Distúrbios do Assoalho Pélvico , Neoplasias do Colo do Útero , Feminino , Humanos , Distúrbios do Assoalho Pélvico/etiologia , Neoplasias do Colo do Útero/radioterapia , Estudos Transversais , Diafragma da Pelve , Qualidade de Vida , Inquéritos e QuestionáriosRESUMO
Recently, the good physical and chemical properties, well-defined pore architectures, and designable topologies have made microporous organic networks (MONs) excellent potential candidates in high-performance liquid chromatography (HPLC). However, their superior hydrophobic structures restrict their application in the reversed-phase mode. To solve this obstacle and to expand the application of MONs in HPLC, we realized the thiol-yne "click" postsynthesis of a novel hydrophilic MON-2COOH@SiO2-MER (MER denotes mercaptosuccinic acid) microsphere for reversed-phase/hydrophilic interaction mixed-mode chromatography. SiO2 was initially decorated with MON-2COOH using 2,5-dibromoterephthalic acid and tetrakis(4-ethynylphenyl)methane as monomers, and MER was then grafted via thiol-yne click reaction to yield MON-2COOH@SiO2-MER microspheres (5 µm) with a pore size of ~1.3 nm. The -COOH groups in 2,5-dibromoterephthalic acid and the post-modified MER molecules considerably improved the hydrophilicity of pristine MON and enhanced the hydrophilic interactions between the stationary phase and analytes. The retention mechanisms of the MON-2COOH@SiO2-MER packed column were fully discussed with diverse hydrophobic and hydrophilic probes. Benefiting from the numerous -COOH recognition sites and benzene rings within MON-2COOH@SiO2-MER, the packed column exhibited good resolution for the separation of sulfonamides, deoxynucleosides, alkaloids, and endocrine-disrupting chemicals. A column efficiency of 27,556 plates per meter was obtained for the separation of gastrodin. The separation performance of the MON-2COOH@SiO2-MER packed column was also demonstrated by comparing with those of MON-2COOH@SiO2, commercial C18, ZIC-HILIC, and bare SiO2 columns. This work highlights the good potential of the thiol-yne click postsynthesis strategy to construct MON-based stationary phases for mixed-mode chromatography.
Assuntos
Alcaloides , Dióxido de Silício , Dióxido de Silício/química , Cromatografia Líquida de Alta Pressão/métodos , Alcaloides/análise , Interações Hidrofóbicas e Hidrofílicas , Compostos de Sulfidrila , Cromatografia de Fase Reversa/métodosRESUMO
Microporous organic networks (MONs) are promising materials for the magnetic solid-phase extraction (MSPE) of trace targets from diverse complex samples. However, all the reported magnetic MONs (MMONs) are mono-functionalized and synthesized by refluxing at high temperatures, which is not an energy-efficient and environmentally friendly method. Here, for the first time, we report the room-temperature fabrication of a novel dual-functionalized MMON (MMON-B) for the efficient MSPE of typical vanillin additives from food samples prior to high-performance liquid chromatography (HPLC). The conjugated MMON-B with numerous -OH and -NH2 groups afforded good extraction for vanillins via π-π, hydrophobic, and hydrogen-bonding interactions. The factors affecting the extraction were studied in detail. Under the optimal conditions, the developed MMON-B-MSPE-HPLC-UV method exhibited wide linear range (0.50-1200 µg L-1), low limits of detection (0.10-0.15 µg L-1), and good reusability and stability. Therefore, MMON-B was successfully used to enrich vanillins in complex food samples. The morphology and extraction efficiency of the room-temperature synthesized MMON-B were comparable with those of the MMON-B synthesized via the conventional reflux method, indicating that the room-temperature fabrication method is a good alternative to the reflux method. This study presents the feasibility of using a room-temperature method for synthesizing dual-functionalized MONs, and the findings may significantly promote the application of MONs in the MSPE of trace targets from complex matrices.
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Alimentos , Magnetismo , Temperatura , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de DetecçãoRESUMO
Microporous organic networks (MONs) are promising in high performance liquid chromatography (HPLC) with large specific surface area, good hydrophobicity and stability. However, their superhydrophobic structures restrict MONs-based HPLC only in reversed-phase mode. To decrease the hydrophobicity of pristine MONs and to expand their broad application in HPLC, here we described the monomer-mediated fabrication of core-shell MON-2COOH@SiO2 microspheres for reversed-phase liquid chromatography (RPLC)/hydrophilic interaction liquid chromatography (HILIC) mixed-mode chromatography for the first time. The -COOH groups were introduced into MONs' skeleton to improve their hydrophilicity and to provide hydrophilic interaction sites. The MON-2COOH was grafted onto silica via a monomer mediated method to produce monodispersed core-shell microspheres. By adjusting the concentration of reactants, the thickness of MON-2COOH shell was easily manipulated. The packed MON-2COOH@SiO2 column showed high resolution and selectivity for separating both hydrophobic (alkylbenzenes, polycyclic aromatic hydrocarbons, anilines and phenols) and hydrophilic (nucleoside and nucleic bases) probes, highlighting the promise of MONs in mixed-mode HPLC. The MON-2COOH@SiO2 column also achieved good separation to sulfonamides, nonsteroidal anti-inflammatory drugs, flavonoids and phenylurea herbicides, and offered better resolution than commercial C18 and pristine SiO2 column. Multiple retention mechanisms were also found on MON-2COOH@SiO2 packed column, underlining the great potential of MONs in mixed-mode HPLC.
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Herbicidas , Hidrocarbonetos Policíclicos Aromáticos , Compostos de Anilina , Anti-Inflamatórios , Cromatografia de Fase Reversa/métodos , Flavonoides , Interações Hidrofóbicas e Hidrofílicas , Microesferas , Nucleosídeos , Fenóis , Dióxido de Silício/química , SulfonamidasRESUMO
Microporous organic networks (MONs) are a booming class of functional materials in elimination of environmental pollutants. However, the limit varieties of MONs still restrict their broad applications. Here we report the synthesis of a novel type of crown ether (CE)-based MONs via the coupling between brominated 18-crown-6 ether and different aromatic alkynyls. The constructed CE-based MONs integrates the good conjugation property of MONs and the inherent host-guest binding sites of CE, allowing the ultrafast and efficient adsorption and removal of a typical environmental priority pollutant 2,4,6-trichlorophenol (2,4,6-TCP). The hydrophobic CE-based MONs can also address the recovery challenge of unstable discrete CE in most organic and inorganic solvents. All CE-based MONs displayed fast adsorption kinetics (< 3 min) and large adsorption capacities (229.1-341.7 mg g-1) for 2,4,6-TCP. The CE-based MONs also gave stable adsorption capacities for 2,4,6-TCP in pH range of 4.0-6.0, NaCl concentration of 0-40 mg L-1, HA concentration of 0-30 mg L-1, or H2O2 ratio of < 5 %. Density functional theory calculation, Fourier transform infrared and X-ray photoelectron spectra evaluation revealed adsorption process involved hydrophobic, π-π and hydrogen bonding interactions. The CE-based MONs also showed favorable reusability and good adsorption for other toxic chlorophenols. This work highlights the potential of CE-based MONs in contaminants elimination.
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Clorofenóis , Éteres de Coroa , Poluentes Ambientais , Poluentes Químicos da Água , Clorofenóis/química , Peróxido de Hidrogênio , Adsorção , Poluentes Ambientais/química , Poluentes Químicos da Água/análiseRESUMO
Microporous organic networks (MONs) have shown great potential in the removal of environmental contaminants. However, all studies have focused on the design and construction of novel and efficient adsorbents, and the recycling and reuse of adsorbates were disregarded. In this study, we report a feasible approach to synthesize renewable and reusable MONs by using target halogenated contaminants such as tetrabromobisphenol A (TBBPA), 2,3-dichlorophenol (2,3-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) as starting monomers. TBBPA, 2,3-DCP, and 2,4,6-TCP acted as hazardous contaminants and starting monomers for MONs, leading to the recycling of both adsorbents and adsorbates. The obtained TBBPA-MON, 2,3-DCP-MON, and 2,4,6-TCP-MON not only offered good reusability and large adsorption capacity for their elimination but also provided good adsorption for other phenolic contaminants relying on multiple interactions. Density functional theory calculation indicated the dominant role of π-π and hydrophobic interactions and the secondary role of hydrogen bonding interactions during the adsorption process. The used TBBPA-MON could be reused and the eluted TBBPA could be recycled and renewed for the construction of fresh MONs. This study provided a feasible approach to design and synthesize renewable MONs for environmental contaminants.
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Fenóis , Adsorção , Ligação de Hidrogênio , Interações Hidrofóbicas e HidrofílicasRESUMO
OBJECTIVE: To compare the morphological and compositional characteristics of carotid plaques in two cohorts (2002-2005 and 2012-2015) of Chinese patients using magnetic resonance vessel wall imaging. METHODS: Symptomatic patients with carotid atherosclerotic plaques who underwent carotid vessel wall magnetic resonance imaging between 2002-2005 and 2012-2015 were retrospectively recruited. Plaque morphology [including mean wall area, wall thickness, and maximum normalized wall index (NWI)] and composition [including calcification, intraplaque hemorrhage, and lipid-rich necrotic core (LRNC)] in symptomatic carotid arteries were evaluated and compared between patients in these two time periods. RESULTS: A total of 258 patients, including 129 patients in the 2002-2005 cohort and 129 patients in the 2012-2015 cohort, were recruited. Statin use (49.6%vs. 32.6%, P = 0.004) and hypertension (76.0% vs. 62.8%, P = 0.015) were significantly more common in the 2012-2015 cohort than in the 2002-2005 cohort. Patients in the 2012-2015 cohort also exhibited significantly low plaque burden parameters (allP < 0.05), as well as a lower prevalence (68.2% vs. 89.9%, P < 0.001) and volume percentages of LRNC (11.2% ± 14.2% vs. 25.7% ± 17.7%, P < 0.001). These differences remained significant after adjustment for clinical factors. The differences in the volume percentages of LRNC also remained significant after an additional adjustment for maximum NWI ( P < 0.001). CONCLUSIONS: Patients in the 2012-2015 cohort had a lower plaque burden and volume percentages of LRNC in symptomatic carotid arteries than those in the 2002-2005 cohort. These findings indicate that carotid plaques in the recent cohort had a lower severity and vulnerability.
RESUMO
As an effective sample pretreatment approach, stir bar sorptive extraction (SBSE) has shown great prospects in static microextraction and selective enrichment. In this work, bifunctional microporous organic network (B-MON) with the coexistence of amino and hydroxyl groups was firstly designed and synthesized as a novel coating for efficient SBSE of parabens and flavors in combination with high-performance liquid chromatography coupled with photodiode array detection (HPLC-PDA). Linked by covalent bonds to form an extension of the aromatic ring skeleton, B-MON was a tailored adsorbent featured by porous structure and abundant hydrogen bonding sites for analytes with benzene/naphthalene rings and OH/COOH groups. The extraction and desorption parameters were evaluated in detail. Under the optimized conditions, the proposed B-MON-SBSE-HPLC-PDA method offered good linearity (0.10-100 µg L-1) with correlation coefficients R2 ≥ 0.995, low limits of detection (0.010-0.035 µg L-1) and limits of quantification (0.035-0.115 µg L-1), and favorable enrichment factors (40-49). Furthermore, the developed method has been applied to the analysis of parabens and flavors in cosmetic and food samples with recoveries ranging from 80.4 to 109.6%. This method was also feasible to extract the analytes with benzene/naphthalene rings and OH/COOH groups, such as the plant growth regulators and non-steroidal anti-inflammatory drugs. The present study provided a new way to synthesize bifunctional MONs for SBSE of trace analytes in complex samples.