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1.
J Chromatogr A ; 1655: 462521, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34509692

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.

2.
ACS Appl Mater Interfaces ; 13(33): 39905-39914, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34374514

RESUMO

The lack of functional groups or binding sites largely hindered the broad application of microporous organic networks (MONs). Herein, we report the fabrication of the sulfonate group-enriched magnetic MON composite (MMON-SO3H@SO3Na) via the combination of the sulfonic acid group containing the monomer and thiol-yne click postmodification for efficient magnetic solid-phase extraction (MSPE) of benzimidazole fungicides (BZDs) from complex sample matrices. The well-defined core-shell-structured MMON-SO3H@SO3Na was obtained and served as an advanced adsorbent for MSPE for concentrating and monitoring trace BZDs. The MMON-SO3H@SO3Na with numerous sulfonate groups provides plenty of ion-exchange, hydrogen-bonding, and π-π sites, leading to the favorable affinity to BZDs via multiple interaction mechanisms. The MMON-SO3H@SO3Na-based MSPE-high-performance liquid chromatography method afforded a wide linear range, low limits of detection, large enrichment factors, good precisions, and reusability for BZDs. Trace BZDs in complex vegetables and fruit samples were successfully detected by the established method. The MMON-SO3H@SO3Na also exhibited good selectivity toward multiple types of polar contaminants containing hydrogen-bonding sites and aromatic structures. This work provided a new postsynthesis strategy for constructing novel and multifunctioned magnetic MONs for preconcentration of trace analytes in a complex matrix.


Assuntos
Alcanossulfonatos/síntese química , Alcinos/química , Benzimidazóis/isolamento & purificação , Análise de Alimentos/métodos , Fungicidas Industriais/isolamento & purificação , Compostos de Sulfidrila/química , Cromatografia Líquida de Alta Pressão/métodos , Química Click , Óxido Ferroso-Férrico/química , Frutas/química , Limite de Detecção , Magnetismo/métodos , Microesferas , Porosidade , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Verduras/química
3.
Talanta ; 233: 122471, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215105

RESUMO

Development of novel functionalized adsorbents for efficient magnetic solid phase extraction (MSPE) is essential for promoting their versatile applications in sample pretreatment. Herein, we report the fabrication of a new polyethyleneimine-600 decorated magnetic microporous organic network nanosphere (Fe3O4@MON-PEI600) for effective MSPE of trace non-steroidal anti-inflammatory drugs (NSAIDs) from different water samples. The core-shelled Fe3O4@MON-PEI600 integrates the synergistic effects of Fe3O4, MON and PEI600, providing facile and effective extraction to NSAIDs via multiple hydrogen bonding, π-π and hydrophobic interactions. The inner MON shell employs π-π and hydrophobic interaction sites and the outer PEI-600 coat acts as the hydrogen bonding doner/receptor, which affords good extraction performance for NSAIDs. Under optimal conditions, the Fe3O4@MON-PEI600-MSPE-HPLC-UV method gives wide linear range (0.14-400 µg L-1), low limits of detection (0.042-0.149 µg L-1), good precisions (intra-day and inter-day RSDs < 4.5%, n = 6), and large enrichment factors (97.0-98.2). Extraction mechanisms and selectivity of Fe3O4@MON-PEI600 are evaluated in detail. Moreover, Fe3O4@MON-PEI600 is successfully applied to enrich the trace NSAIDs in different water samples with the concentrations of 0.7 and 0.8 µg L-1 for 1-naphthylacetic acid, 0.5 and 0.1 µg L-1 for naproxen as well as 0.7 µg L-1 for ibuprofen, respectively. The developed method not only affords a novel and efficient magnetic adsorbent for NSAIDs in aqueous media at trace level, but also provides a new strategy for the rational design and synthesis of multiple functionalized MON composites in sample pretreatment.


Assuntos
Nanosferas , Preparações Farmacêuticas , Adsorção , Anti-Inflamatórios não Esteroides , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Fenômenos Magnéticos , Polietilenoimina , Extração em Fase Sólida , Águas Residuárias
4.
J Chromatogr A ; 1651: 462347, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34166861

RESUMO

Herein, we report the fabrication of a novel, well-defined core-double-shell-structured magnetic Fe3O4@polydopamine@naphthyl microporous organic network (MON), Fe3O4@PDA@NMON, for the efficient magnetic extraction of hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and p-nitrophenol (p-Npn) from wastewater samples. The hierarchical nanospheres were designed and constructed with the Fe3O4 nanoparticle core, the inner shell of a polydopamine (PDA) layer, and the outer shell of a porous naphthyl MON (NMON) coating, allowing efficient and synergistic extraction of OH-PAHs and p-Npn via hydrophobic, hydrogen bonding, and π-π interactions. The Fe3O4@PDA@NMON nanospheres were well characterized and employed as an efficient sorbent for magnetic solid-phase extraction (MSPE) coupled with high performance liquid chromatography (HPLC) for analyzing of OH-PAHs and p-Npn. Under optimal conditions, the Fe3O4@PDA@NMON-based-MSPE-HPLC-UV method afforded wide linear range (0.18-500 µg L-1), low limits of detection (0.070 µg L-1 for p-Npn, 0.090 µg L-1 for 2-OH-Nap, 0.090 µg L-1 for 9-OH-Fluo and 0.055 µg L-1 for 9-OH-Phe, respectively), large enrichment factors (92.6-98.4), good precisions (intra-day and inter-day relative standard deviations (RSDs); <6.4%, n=6) and less consumption of the adsorbent. Furthermore, trace OH-PAHs and p-Npn with concentrations of 0.29-0.80 µg L-1 were successfully detected in various wastewater samples. Fe3O4@PDA@NMON also functioned as a good adsorbent to enrich a wide scope of trace contaminants containing hydrogen bonding sites and aromatic structures, highlighting the potential of functional MONs in sample pretreatment.


Assuntos
Indóis/química , Nanosferas/química , Nitrofenóis/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Polímeros/química , Extração em Fase Sólida/métodos , Águas Residuárias/química , Cromatografia Líquida de Alta Pressão , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Fenômenos Magnéticos , Nitrofenóis/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Porosidade
5.
Electrophoresis ; 42(19): 1936-1944, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34180069

RESUMO

Microporous organic networks (MONs) that exhibit good stability and hydrophobicity are promising candidates for performing HPLC separation of small organic compounds. However, their applications in separating large analytes as well as biomolecules are still limited by the microporous nature of MONs. Herein, we demonstrated the fabrication of a MON-functionalized silica (MON@SiO2 ), exhibiting micro and mesopores for the HPLC separations of small drugs as well as large analytes, such as flavones, nonsteroidal anti-inflammatory drugs (NSAIDs), endocrine disrupting chemicals (EDCs), and proteins. MON was successfully modified on SiO2 microspheres to yield the uniform and mono-dispersed MON@SiO2 . The separation mechanisms and performance of the MON@SiO2 packed column were evaluated for a wide range of analytes, including neutral, acidic, basic compounds, drugs, and proteins. Compared with commercial C18 and SiO2 -NH2 packed columns, the proposed MON@SiO2 column afforded superior performance in the separations of flavones, NSAIDs, EDCs, and proteins. Moreover, the MON@SiO2 column also offered good repeatability with intraday RSDs (n = 7) of <0.1%, <2.0%, <2.3%, and <0.7% for the retention time, peak height, peak area, and half peak width, respectively, for separating EDCs. This work proved the potential of using MONs in the HPLC separations of drugs and proteins.

6.
J Chromatogr A ; 1640: 461947, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33556684

RESUMO

Fabrication of novel coatings continues to be an area of great interest and significance in the development and application of stir bar sorptive extraction (SBSE). In this work, a carboxyl-enriched microporous organic network (MON-2COOH) coated stir bar was designed and fabricated as a novel adsorbent for efficient extraction of four phenylurea herbicides (PUHs) before their determination by high-performance liquid chromatography coupled with photodiode array detector (HPLC-PDA). The MON-2COOH was represented as an effective adsorbent for PUHs due to its large surface area, rigid porous structure, aromatic pore walls and the desired hydrogen bonding sites of introduced carboxyl groups. Variables affecting the SBSE of target analytes were optimized in detail. Under the optimal extraction conditions, favorable correlation coefficients (R2 > 0.996) in the linear range 0.10-250 µg L-1, low limits of detection (LODs, S/N = 3) of 0.025-0.070 µg L-1 and good enrichment factors (46-49) were obtained. Besides, the proposed SBSE-HPLC-PDA method was successfully applied to determine trace PUHs in food and environmental water samples with recoveries in the range of 80.0-104.8% and the precisions (relative standard deviations, RSDs) lower than 9.9% (n = 3). This work revealed the potential of MONs in SBSE of trace contaminants from environmental samples.


Assuntos
Análise de Alimentos , Herbicidas/análise , Compostos de Fenilureia/análise , Água/química , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Limite de Detecção , Lycopersicon esculentum/química , Malus/química , Espectroscopia Fotoeletrônica , Porosidade , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Fatores de Tempo , Poluentes Químicos da Água/análise
7.
Talanta ; 224: 121876, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379085

RESUMO

Development of efficient adsorbents for the enrichment of trace contaminants from complex matrix still remains great challenge and interest. Here we report the decoration of amino microporous organic network on zeolitic imidazolate framework (ZIF)-67 derived nitrogen-doped carbon (Co@NC-MON-2NH2) for efficient magnetic solid phase extraction (MSPE) of plant growth regulators (PGRs) from vegetables. The ZIF-67 was calcined to produce Co and N co-doped porous carbon (Co@NC), serving as the magnetic separation module and the core for in-situ growth of MON-2NH2 shell. The Co@NC-MON-2NH2 owned large surface area, good magnetic property and stability, giving high affinity to PGRs via multiple extraction mechanisms such as hydrogen bonding, π-π and hydrophobic interactions. Under optimal conditions, the Co@NC-MON-2NH2 based MSPE-HPLC-UV method gave wide linear range, good precisions, large enrichment factors, less adsorbent consumption and low limit of detections for the studied PGRs. The proposed MSPE-HPLC-UV method was also successfully applied to monitor the trace PGRs in diverse vegetables. These results not only revealed the promise of Co@NC-MON-2NH2 in extraction and adsorption of environmental contaminants from complex matrix, but also provided a new way to fabricate magnetic functionalized MONs in environmental science.


Assuntos
Zeolitas , Carbono , Limite de Detecção , Fenômenos Magnéticos , Nitrogênio , Reguladores de Crescimento de Plantas , Extração em Fase Sólida
8.
Talanta ; 224: 121914, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379116

RESUMO

Microporous organic networks (MONs) have shown great promise in separation science recently. Exploring novel, simple and convenient strategy to fabricate MONs coated capillary columns for gas chromatography (GC) still remains challenging but desirable for the development of MONs in chromatographic separation. To extend the potential application of MONs in separation science and to further develop novel method for the fabrication of MONs-based capillary columns, here we demonstrate a novel covalent coupling strategy to fabricate uniform MONs bonded capillary columns for GC separation of position isomers and hydrocarbons. The bare capillary column was firstly modified with (3-bromopropyl)trimethoxysilane to provide bromine sites for coupling with alkynyl monomers. The amino- and hydroxyl-functionalized MONs (MON-NH2 and MON-OH) were then directly grown onto the inner wall of the brominated capillary columns via the covalent coupling between bromine and alkynyl groups. The uniform MON-NH2 and MON-OH bonded capillary columns were obtained and showed good resolution for GC separation of dichlorobenzene, chlorotoluene, bromotoluene, and propylbenzene position isomers and many other hydrocarbons including linear alkanes, alkylbenzenes, pinene isomers, cyclohexane and benzene, ketones and aldehydes. The MONs bonded capillary columns also owned good lifetime and precision for dichlorobenzene isomers with the relative standard deviations (RSDs) of 0.2-0.3%, 1.2-2.1%, and 1.7-2.5% for retention time, peak height and peak area, respectively. In addition, the fabricated MON-NH2 and MON-OH bonded capillary columns offered better resolution than commercial InertCap-1, InertCap-5, InertCap-1701 and InertCap-WAX capillary columns for the separation of chlorotoluene and bromotoluene position isomers. These results revealed the feasibility of covalent coupling strategy to fabricate MONs-based stationary phases in GC, highlighting the potential of MONs in separation science.

9.
Talanta ; 219: 121209, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887113

RESUMO

Theranostic nano-drug delivery systems are promising candidates for early diagnosis and treatment of tumors. However, it is a great challenge to achieve accurate intracellular delivery and stimuli-responsive drug release with the enhanced anti-tumor effects and reduced side effects. Herein we report the fabrication of polyamide-amine (PAMAM) dendrimer grafted persistent luminescence nanoparticles (PLNPs) via in situ growth of PAMAM on the surface of PLNPs and its application in targeted bioimaging and drug delivery. The developed PLNPs-PAMAM possesses strong renewable near-infrared persistent luminescence for imaging and gives abundant terminal groups for further functionalization. Aptamer AS1411 coupled to the PLNPs-PAMAM surface can specifically bind to the over-expressed nucleolin on the membrane of tumor cells and improve the intracellular accumulation of the nanoparticles. Doxorubicin (DOX) is loaded on PLNPs-PAMAM by a pH-sensitive hydrazine, can be specifically released in the intracellular acid environment, leading to apoptosis of HeLa tumor cells and inhibition of tumor growth. The as-prepared smart drug delivery nanoplatform with persistent luminescence, PLNPs-PAMAM-AS1411/DOX, shows a good application prospect for precise cancer theranostics.


Assuntos
Dendrímeros , Nanopartículas , Neoplasias , Preparações Farmacêuticas , Doxorrubicina/uso terapêutico , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Humanos , Luminescência , Neoplasias/tratamento farmacológico
10.
Angew Chem Int Ed Engl ; 59(40): 17607-17613, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32497359

RESUMO

Design of stable adsorbents for selective gold recovery with large capacity and fast adsorption kinetics is of great challenge, but significant for the economy and the environment. Herein, we show the design and preparation of an irreversible amide-linked covalent organic framework (COF) JNU-1 via a building block exchange strategy for efficient recovery of gold. JNU-1 was synthesized through the exchange of 4,4'-biphenyldicarboxaldehyde (BA) in mother COF TzBA consisting of 4,4',4''-(1,3,5-triazine-2,4,6-triyl)trianiline (Tz) and BA with terephthaloyl chloride. The irreversible amide linked JNU-1 gave good stability, unprecedented fast kinetics, excellent selectivity and outstanding adsorption capacity for gold recovery. X-ray photoelectron spectroscopy along with thermodynamic study and quantum mechanics calculation reveals that the excellent performance of JNU-1 for gold recovery results from the formation of hydrogen bonds C(N)-H⋅⋅⋅Cl and coordinate interaction of O and Au. The rational design of irreversible bonds as both inherent linkage and functional groups in COFs is a promising way to prepare stable COFs for diverse applications.

11.
Chempluschem ; 85(5): 828-831, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32364333

RESUMO

Development of efficient adsorbents for nitrate removal is vital for tackling increasing nitrate contamination. We report a free-radical polymerization strategy to prepare a cationic surfactant-modified covalent organic framework (DhaTab-S) for removing nitrate ions from aqueous solution. DhaTab-S was prepared by grafting a cationic surfactant diallyldimethylammonium chloride solution on vinyl-containing COF (DhaTab-V). The adsorption capacity for nitrate was pH-dependent with the maximum at pH 6, and the adsorption process was largely influenced by ionic strength. The adsorption equilibrium for nitrate on DhaTab-S was reached within 40 minutes and followed pseudo-second-order kinetics. DhaTab-S showed a nitrate adsorption capacity of 108.8 mg g-1 , which is about 15 times that of COF before surfactant modification. The large adsorption capacity makes DhaTab-S a promising candidate for nitrate removal from aqueous media.

12.
ACS Appl Mater Interfaces ; 12(4): 4954-4961, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31894954

RESUMO

Microporous organic networks (MONs) have shown great potential in diverse domains recently. However, the application of MONs in chiral separation or catalysis has been largely lagged due to the lack of chiral MONs and the challenge to synthesize chiral MONs. Here we report a facile thiol-yne click strategy to post-synthesize chiral MONs for the first application in chiral gas chromatography. Three chiral MONs with different chiral centers were rationally designed and synthesized to fabricate their capillary columns for gas chromatographic resolution of various chiral compounds with better resolution than three commercial chiral capillary columns. These results show the great potential of the thiol-yne click strategy for constructing newly chiral MONs and their application in chiral separation.

13.
Anal Chem ; 92(1): 1179-1188, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31818096

RESUMO

Multifunctional nanoprobes with both imaging and drug delivery capabilities represent an emerging approach to the diagnosis and treatment of tumor. However, poor accumulation in tumor cells and low drug availability are the main limitations for their further application. Here we show a pH-driven targeting nanoprobe with dual-responsive drug release for persistent luminescence imaging and chemotherapy of tumor. The nanoprobe is constructed by conjugating the pH-low-insertion-peptide (pHLIP) to the surface of the core-shell structure of mesoporous silica-coated persistent luminescence nanoparticles (MSPLNPs) with the peptide GFLG and disulfide bond as bridges. The pHLIP functionalized nanoprobe exhibits higher cellular uptake for A549 and HepG2 cells in an acidic extracellular microenvironment (pH < 6.5) than in normal physiological condition (pH 7.4). The nanoprobe possesses well-defined NIR persistent luminescence performance and can be effectively accumulated in the tumor site, leading to the visual HepG2 tumor target imaging without autofluorescence interference. Furthermore, the nanoprobe realizes the dual-responsive release of doxorubicin loaded in the mesoporous channels in systems containing cathepsin B and glutathione, and can effectively kill tumor cells and inhibit the growth of tumor. This integrated nanoprobe possesses great potential for the diagnosis and treatment of tumors with high specificity and efficiency.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Materiais Biocompatíveis/química , Doxorrubicina/farmacologia , Nanopartículas/química , Imagem Óptica , Células A549 , Animais , Antibióticos Antineoplásicos/química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Luminescência , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Peptídeos/química , Peptídeos/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Microambiente Tumoral/efeitos dos fármacos
14.
Talanta ; 208: 120434, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816685

RESUMO

In this work, the carboxyl functionalized microporous organic network (MON-COOH) was synthesized as an efficient adsorbent to fabricate solid phase extraction (SPE) column for the extraction of p-nitrophenol, p-chlorophenol, 2,6-dichlorophenol and 2,3-dichlorophenol from water samples, followed by their analysis with high performance liquid chromatography (HPLC). The obtained MON-COOH was characterized with solid 13C nuclear magnetic resonance spectroscopy, fourier transform infrared spectroscopy, thermogravimetric analysis, N2 adsorption-desorption isotherms, scanning electron microscope and water contact angle experiments. The integrating of carboxyl groups into aromatic MON's networks led to their good enrichment for the studied phenols. The hydrogen binding, π-π and hydrophobic interactions played key roles during the extraction. Effects of adsorbents type, desorption solvent and volume, pH and ionic strength were studied. Under the optimal extraction conditions, the MON-COOH column for SPE coupled with HPLC for the determination of the selected four phenols gave the linear range of 0.5-1000 µg L-1, the limit of detections (LODs, S/N = 3) of 0.13-0.62 µg L-1, the limit of quantifications (LOQs, S/N = 10) of 0.43-2.06 µg L-1, the enhancement factors of 113-216, and the intra-day, inter-day and column-to-column precisions (relative standard deviations, RSDs) of 2.8-6.1, 4.1-8.7 and 6.7-10.3%, respectively. The developed method was successfully applied to the analysis of phenols in wastewater samples with the recoveries of 80.3-99.5%. These results revealed the potential of functional MONs as efficient adsorbents in sample pretreatment.

15.
Talanta ; 206: 120179, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514881

RESUMO

In this work, the magnetic amino-functionalized microporous organic network composites (Fe3O4@MON-NH2) were rational designed and facile synthesized for magnetic solid phase extraction (MSPE) of endocrine disrupting chemicals (EDCs), followed by their analysis with high-performance liquid chromatography. The incorporation of amino groups (hydrogen bonding sites) into hydrophobic MON-NH2 networks led to their good enrichment for four typical EDCs bisphenol A (BPA), 4-alpha-cumylphenol (4-α-CP), 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) relying on the pre-designed hydrogen bonding, π-π and hydrophobic interactions. The combination of MON-NH2 shell and magnetic Fe3O4 core provided a fast extraction of BPA, 4-α-CP, 4-t-OP and 4-NP from matrix solution. Under the optimal conditions, the developed method offered good linearity (R2 > 0.990) in the range of 0.05-1000 µg L-1, low limits of detection (S/N = 3) of 0.015-0.030 µg L-1 and large enrichment factors of 172-197 for the studied EDCs. The maximum adsorption capacities of BPA, 4-α-CP, 4-t-OP and 4-NP were 124.1, 105.6, 116.6 and 117.9 mg g-1, respectively. The Fe3O4@MON-NH2 gave larger selectivity for other polar phenols than non-polar polycyclic aromatic hydrocarbons, revealing the dominant role of hydrogen bonding interaction during the extraction and the potential of Fe3O4@MON-NH2 for other polar phenols. The developed method was successfully applied for the analysis of EDCs in water, orange juice and beverage bottle samples with the recoveries of 80.3-109.5%. These results revealed the potential of functional MONs as efficient adsorbents in sample pretreatment.


Assuntos
Disruptores Endócrinos/análise , Contaminação de Alimentos/análise , Nanopartículas de Magnetita/química , Poluentes Químicos da Água/análise , Adsorção , Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão , Citrus sinensis/química , Embalagem de Alimentos , Sucos de Frutas e Vegetais/análise , Lagos/análise , Limite de Detecção , Fenóis/análise , Rios/química , Extração em Fase Sólida/métodos
16.
ACS Appl Mater Interfaces ; 11(49): 46219-46225, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31738503

RESUMO

We report a thiol-ene click strategy for the preparation of a novel phenylboronic acid-functionalized covalent organic framework (COF) for selective removal of catechol in aqueous solution. Vinyl-functionalized 2,5-diallyloxyterephthalaldehyde (Da-V) was prepared as a building ligand. Da-V was then condensed with 1,3,5-tris(4-aminophenyl)benzene (Tab) to give a vinyl-functionalized COF DhaTab-V. Subsequently, 4-mercaptophenylboronic acid (4-MPBA) was covalently linked on DhaTab-V via thiol-ene click reaction to give phenylboronic acid-functionalized COF DhaTab-PBA. The adsorption isotherms, energetics and kinetics, and reusability of DhaTab-PBA for the adsorption and removal of catechol from aqueous solution were investigated in detail. This phenylboronic acid-functionalized COF is promising as sorbent for selective removal of catechol from aqueous medium with large adsorption capacity and good reusability.

17.
J Chromatogr A ; 1608: 460420, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31405571

RESUMO

Chiral crystalline sponges (CCSs) are a recent class of chiral porous metal complexes potential in chiral recognition. Here we report the fabrication of polysiloxane OV-1701 incorporated CCS-3S (PSO/CCS-3S) coated capillary column as a novel stationary phase for gas chromatographic separation of diverse racemates. CCS-3S with the chiral ligand of (S)-mandelic was selected as the model CCS. With the aid of polysiloxane OV-1701, PSO/CCS-3S coated capillary column gave improved resolution, broader enantiomers separation scope and much larger McReynolds constants than CCS-3S coated capillary column. Many racemates that cannot be separated on CCS-3S coated capillary column were well resolved on PSO/CCS-3S coated capillary column. The PSO/CCS-3S coated capillary column also gave wide linear range, low limit of detection, good repeatability and reproducibility, and fine inertness and anti-column bleeding properties for the separation of enantiomers. In addition, the PSO/CCS-3S coated capillary column presented better resolution for the studied racemates than commercial ß-cyclodextrin based Cyclosil B (30 m long ×0.32 mm i.d. × 0.25 µm film thickness), ß-DEX 225 (30 m long ×0.25 mm i.d. × 0.25 µm film thickness) and amino acid based Chirasil L-Val (25 m long ×0.25 mm i.d. × 0.12 µm film thickness) capillary columns. These results indicate the great potential of PSO/CCS-3S coated capillary column in separation of enantiomers.


Assuntos
Cromatografia Gasosa/instrumentação , Siloxanas/química , Cromatografia Gasosa/métodos , Compostos Orgânicos/química , Compostos Orgânicos/isolamento & purificação , Reprodutibilidade dos Testes , Estereoisomerismo , beta-Ciclodextrinas/química
18.
Talanta ; 204: 224-228, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357286

RESUMO

Gold nanoparticles (AuNPs) without surface capping agents are easily aggregated owing to their high surface energy, leading to an unexpected decrease of their catalytic activity. Herein, we report gold nanoparticles decorated covalent organic framework (COF) as mimetic peroxidase for colorimetric detection of mercury. 1,3,5-Tris-(4-formyl-phenyl)triazine (PT) and 4, 4'-azodianiline (Azo) was employed as the monomers to prepare a novel imine based COF PTAzo under solvothermal conditions. AuNPs are further decorated into the PTAzo to form COF-AuNPs hybrid via a citrate reducing method. The COF-AuNPs show high stability, and exhibits enhanced peroxidase mimetic activity in the presence of Hg2+. The Hg2+ concentration dependent peroxidase mimetic activity of COF-AuNPs enables the development of a sensitive and selective method for detection of Hg2+ in aqueous solution. The developed method gives good linearity in the range of 5-300 nM with the limit of detection of 0.75 nM. The results show that Hg2+-enhanced peroxidase mimetic activity of COF-AuNPs offers great potential for the detection of Hg2+ in real samples.

19.
Chem Commun (Camb) ; 55(36): 5283-5286, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993283
20.
Electrophoresis ; 40(16-17): 2186-2192, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30942493

RESUMO

Microporous organic networks (MONs) are a new class of porous materials synthesized via Sonogashira coupling reactions between organic building blocks. Here we report an in situ synthesis approach to fabricate MONs coated capillary column for high resolution GC separation of hydrocarbons. The McReynolds constant evaluation reveals the MONs coated capillary is a non-polar column. The MONs coated capillary column shows good resolution for GC separation of diverse important industrial hydrocarbons such as linear and branched alkanes, alkylbenzenes, pinene isomers, ethylbenzene and styrene, cyclohexane and benzene. The MONs coated capillary column gave a high column efficiency of 1542 plates per meter for hexane and good precision for replicate separations of the selected hydrocarbons with the RSDs of 0.2-0.3, 1.5-3.1, and 1.9-3.3% for retention time, peak height and peak area, respectively. The MONs coated capillary also offered better resolution than commercial Inert Cap-1 and Inert Cap-5 capillary columns for hexane and heptane isomers. These results reveal the potential of MONs as novel stationary phases in GC.


Assuntos
Cromatografia Gasosa/métodos , Hidrocarbonetos , Hidrocarbonetos/análise , Hidrocarbonetos/química , Hidrocarbonetos/isolamento & purificação , Compostos Orgânicos/química , Porosidade , Temperatura
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