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1.
J Chromatogr A ; 1619: 460913, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32007220

RESUMO

Traditional boron affinity materials usually capture cis-diol-containing molecules under alkaline condition, but some cis-diol-containing molecules, such as polyphenols, are unstable and easy to be oxidized and degraded under alkaline condition. Teamed boronate affinity (TBA) can specifically capture cis-diol-containing molecules under neutral condition. However, the report about combination of TBA and magnetic nanoparticle for the extraction was rare. Here, we fabricated two kinds of teamed boronate affinity magnetic nanoparticles (TBAMP), including Fe3O4@TBAP and Fe3O4@SiO2@TBAP. Adsorption capacities of cis-diol-containing molecules on the latter were similar to these on the former, but the latter possessed more superior regeneration performance than the former. Therefore, the TBAMP with more superior regeneration performance was used as magnetic solid-phase extraction (MSPE) adsorbent for capturing polyphenols under neutral condition. The TBAMP MSPE was optimized in detail, and combined with high-performance liquid chromatography-mass spectrometry (HPLC-MS) for the simultaneous determination of 13 kinds of polyphenols from Flos Lonicerae Beverage. The proposed method showed low limit of detection between 0.01 and 0.20 ng mL-1. In blank Flos Lonicerae Beverage, 11 kinds of polyphenols ranged from 0.54 ng mL-1 to 52.99 ng mL-1 were detected. In the standard addition method, recoveries of cis-diol-containing polyphenols were between 85.7% and 102.1% with intra-day and inter-day relative standard deviation ranging from 3.2% to 5.1% and 5.3% to 7.3%, respectively.

2.
J Chromatogr A ; 1609: 460448, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31421793

RESUMO

In this work, we reported a simple two-step method for the synthesis of magnetic mesoporous epoxy resin (MMER), including one-pot template-free hydrothermal synthesis of nanoscale amine-functionalized magnetic nanoparticles (MN-NH2) and initiator-free ring-opening polymerization of epoxy resin. The resultant MMER was characterized in detail by transmission electron microscope (TEM), Fourier transform-infrared (FT-IR) spectra, X-ray photoelectron spectroscopy (XPS), thermogravimetic analysis (TGA) and magnetization curves. These results demonstrated successful synthesis of MMER with sufficient magnetic property and excellent thermal stability. The epoxy resin was covalent bonding MN-NH2 on and synthesized by hydrophobic monomers, so the MMER exhibited excellent adsorption quantity for hydrophobic bile acids. The MMER was used as magnetic solid-phase extraction (MSPE) sorbent, and combined with liquid chromatography-tandem mass spectrometry to extract and monitor 11 kinds of bile acids from serum sample. The proposed MSPE combined with LC-MS/MS method exhibited low limit of detection between 0.1 and 5 ng mL-1. In blank serum sample, 9 kinds of bile acids were detected, and ranged from -2.29 ng mL-1 to 6.86 ng mL-1. In standard addition recovery test, the recovery values of detectable bile acids ranged 102.4% to 108.5%, 96.0% to 104.0% and 82.3% to 103.3% when spiked with 0.2, 2.0 and 20 ng mL-1, respectively. The intra- and inter-day precision (n = 6) ranged 3.7% to 5.9% and 7.0% to 9.5%, respectively. The above results demonstrated that the MSPE combined with LC-MS/MS method was accurate and effective for quantitative determination of bile acids from complex biological samples.


Assuntos
Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/isolamento & purificação , Resinas Epóxi/química , Fenômenos Magnéticos , Polimerização , Adsorção , Cromatografia Líquida , Humanos , Limite de Detecção , Nanopartículas/química , Nanopartículas/ultraestrutura , Porosidade , Extração em Fase Sólida , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem
3.
J Chromatogr A ; 1609: 460510, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31515077

RESUMO

In this study, a novel phenyl-boronic acid polymeric monolith (PBAPM) in polyether ether ketone (PEEK) tube was fabricated. The inner wall of PEEK tube was modified with mussel inspired polydopamine layer to firmly bond PBAPM, so as to avoid the outflow of PBAPM from PEEK tube and improve the service life and application scope of PBAPM. The PBAPM was synthesized by initiator-free ring-opening polymerization based on our previous work. The boric acid groups provided B-N coordination sites, as well as the hydrophobic amino and epoxy monomers provided hydrophobic interaction sites. Due to the synergistic effect of hydrophobic interaction and B-N coordination, the PBAPM exhibited excellent binding amounts for nitrogen-containing sulfonamides (SAs). In addition, the PBAPM possessed excellent stability, rigidity and permeability. Therefore, the PBAPM was used as solid phase microextraction (SPME) material for enrichment and separation of SAs from aqueous samples. The PBAPM SPME was optimized in detail, and combined with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis for simultaneous determination of 10 kinds of SAs from tap, lake and river water. Using only 1 mL of water samples, limit of quantitation of SAs could reach 0.54-4.5 ng L-1. Recoveries of standard spiked SAs from water samples were between 82.0% and 105.4%, with intra-day and inter-day relative standard deviation ranging from 3.3% to 5.6% and 4.2% to 8.1%, respectively. The PBAPM SPME combined with UPLC-MS/MS method shown better or similar recoveries, and used fewer samples than previous methods. These results demonstrated that the PBAPM could selectively separate and enrich ultra-trace nitrogen-containing SAs from aqueous samples.


Assuntos
Ácidos Borônicos/química , Cromatografia Líquida de Alta Pressão/métodos , Polimerização , Polímeros/química , Microextração em Fase Sólida , Sulfonamidas/análise , Espectrometria de Massas em Tandem/métodos , Sulfonamidas/química , Água/química , Poluentes Químicos da Água/análise
4.
J Chromatogr A ; 1590: 10-18, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30609959

RESUMO

Boronate affinity materials are usually used for selective enrichment of cis-diol-containing compounds, mainly based on formation of pH-dependent cyclic ester between cis-diol and boronic acid. Recently, B-N coordination, or combined with hydrogen-bonding interaction, was employed as primary interaction for the extraction of nitrogen-containing compounds. However, there are no reports about the combination of hydrophobic (or π-π) interaction and B-N coordination for the extraction. Here, we prepared a novel hydrophobic phenyl-boronic acid polymer (PBAP) through initiator-free ring-opening polymerization. The adsorption experiment indicated that the PBAP could combine hydrophobic (or π-π) interaction and B-N coordination to enhance their adsorption capacity toward hydrophobic and nitrogen-containing compounds, for example sulfamethoxazole (SMX) and trimethoprim (TMP). In addition, the PBAP monolith synthesized in pipette tip was used as solid phase microextraction (SPME) sorbent with combination of ultra high performance liquid chromatography to extract and monitor SMX and TMP from animal-originated foodstuffs. The proposed method exhibited low limit of quantitation as 5.0 and 1.0 ng mL-1 for SMX and TMP, respectively. The recoveries at three spiked levels were between 92.4% to 100.5% for SMX, and 92.7% to 102.6% for TMP, with intra-day and inter-day relative standard deviations no more than 5.3% and 8.6%, respectively. These results well demonstrated that the combination of hydrophobic (or π-π) interaction and B-N coordination played an important role in the extraction of hydrophobic and nitrogen-containing compounds.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas , Produtos da Carne/análise , Microextração em Fase Sólida/métodos , Sulfametoxazol , Trimetoprima , Ácidos Borônicos/química , Resíduos de Drogas/análise , Resíduos de Drogas/química , Resíduos de Drogas/isolamento & purificação , Polímeros/química , Sulfametoxazol/análise , Sulfametoxazol/química , Sulfametoxazol/isolamento & purificação , Trimetoprima/análise , Trimetoprima/química , Trimetoprima/isolamento & purificação
5.
J Chromatogr A ; 1544: 23-32, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29499841

RESUMO

A combination between modification with porous layer and grafting of polyethyleneimine (PEI) on the inner face of capillary was for the first time developed for boronate affinity in-tube solid-phase microextraction (SPME) material to enhance the extraction capacity for cis-diol-containing polyphenols. The successful synthesis of boronate-decorated polyethyleneimine-grafted porous layer open tubular (BPPLOT) capillary was confirmed by scanning electron micrograph, Fourier transform-infrared spectra and absorption experiments. The porous layer, PEI and boronate affinity provided high specific surface area, more binding sites for boronate groups and specific selectivity of BPPLOT capillary, respectively. The maximum binding quantity of BPPLOT capillary greatly improved, and ranged from 143 to 170 µg m-1 for cis-diol-containing polyphenols (catechin, chlorogenic acid, caffeic acid and epicatechin). A green method based on boronate affinity in-tube SPME was developed for separation and enrichment polyphenols, and some parameters of in-tube SPME were optimized. After in-tube SPME, HPLC with UV detection was used for quantitative determination of polyphenols. Recoveries of standard spiked cis-diol-containing polyphenols from fruit juice were between 80.9% and 102%, with intra-day and inter-day coefficient of variation ranging from 4.8% to 7.3% and 5.0% to 8.6%, respectively. Conversely, recovery of non-cis-diol-containing ferulic acid was no greater than 3.0%. These results suggested that the BPPLOT capillary could effectively separate and enrich cis-diol-containing polyphenols from real samples.


Assuntos
Ácidos Borônicos/química , Sucos de Frutas e Vegetais/análise , Polietilenoimina/química , Polifenóis/isolamento & purificação , Álcoois/química , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Cinética , Porosidade , Microextração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Chá/química , Temperatura
6.
Anal Bioanal Chem ; 410(1): 247-257, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29098333

RESUMO

In this work, we reported an effective method for the synthesis of a multirecognition magnetic molecularly imprinted polymer (MMIP) with atom transfer radical polymerization (ATRP), using 2,4-diamino-6-methyl-1,3,5-triazine as pseudo-template. The resulting MMIP was characterized in detail by Fourier transform-infrared (FT-IR) spectra, scanning electron microscopy (SEM), thermogravimetic analysis (TGA), and vibrating sample magnetometry (VSM). These results indicated the successful synthesis of MMIP with sufficient thermal stability and magnetic properties. The adsorption experiments were carried out to evaluate the specific selectivity of MMIP related to the spatial structure of target molecules. The MMIP exhibited multirecognition ability and excellent binding capability for melamine (MEL), cyromazine (CYR), triamterene (TAT), diaveridine (DVD), and trimethoprim (TME), and the apparent maximum number of binding sites (Q max) was 77.5, 75.2, 72.5, 69.9, and 70.4 µmol g-1, respectively. The multirecognition MMIP not only possessed adequate magnetic responsiveness for fast separation but also avoided the risk of template leakage on trace component analysis. Therefore, it was suitable for serving as a magnetic solid-phase extraction (MSPE) adsorbent. MSPE coupled with high-performance liquid chromatography analysis was applied to enrich and separate five target molecules from three samples. Recoveries for all target molecules ranged from 81.6 to 91.5% with relative standard deviations of no more than 4.1% (n = 3). Graphical abstract Multirecognition property of magnetic molecularly imprinted polymer prepared with pseudo template.

7.
J Chromatogr A ; 1516: 125-130, 2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-28826619

RESUMO

Cell membrane chromatography (CMC) is an effective tool in screening active compounds from natural products and studying membrane protein interactions. Nevertheless, it always consumes a large amount of cells (e.g. 107-108) for column preparation. To overcome this, micro-CMC (mCMC), that employs a silica capillary as membrane carrier, was developed. However, both CMC and mCMC suffer from short column life span (e.g. 3days), mainly due to the falling-off of cellular membranes (CMs). This has greatly limited further application of CMC and mCMC, especially when the cells are hard to obtain. To solve this, N-hydroxysuccinimide (NHS)-modified silica-based porous layer open tubular capillary was first prepared for mCMC. The NHS groups can easily react with amino groups on CMs to form a stable covalent bond under a mild condition. So, CMs immobilized on the NHS-modified capillary are less likely to fall off. To verify this, SKBR3/mCMC (Her2 positive) and BALL1/mCMC (CD20 positive) columns were prepared. Two monoclonal antibody drugs, trastuzumab (anti-Her2) and rituximab (anti-CD20), were selected as analytes to characterize the columns. As a result, NHS-modified column for mCMC can afford higher chromatographic retention than non-modified column. Besides, the column life span was significantly improved to more than 16days for SKBR3/mCMC and 14days for BALL1/mCMC, while the compared column showed a sharp decline in retention factor in first 3days.


Assuntos
Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Cromatografia/instrumentação , Dióxido de Silício/química , Porosidade , Rituximab/análise , Succinimidas/química , Trastuzumab/análise
8.
J Chromatogr A ; 1509: 1-8, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28629938

RESUMO

A combination between modification with nanoparticles (NP) and oriented antibody immobilization (OAI) on the inner face of capillary was for the first time developed for immunoaffinity in-tube solid-phase microextraction (SPME) to promise high antigen extraction capacity. ß2-microglobin (ß2MG) and cystatin C (Cys-C) were selected as model antigens. Poly(glycidyl methacrylate) (PGMA) NPs were chemically immobilized onto the capillary by a ring-opening reaction. Antibodies for ß2MG and Cys-C were immobilized on the NPs through OAI. Scanning electron micrograph of the OAI capillary clearly showed that the PGMA NPs were coated onto the inner surface of capillary in a dense monolayer. In addition, random antibody immobilized (RAI) capillaries and OAI capillaries without NP were also prepared as controls. The extraction capacities of OAI capillaries were 2.02 and 2.18mgm-1 for ß2MG and Cys-C, and were about 5 and 6 times as many as RAI capillaries and OAI capillaries without NP, respectively. The resultant capillaries were used as in-tube SPME materials to enrich ß2MG and Cys-C for particle-enhanced turbidimetric immunoassay. When using 1.0mgL-1 standard solutions, the recoveries of OAI capillaries, RAI capillaries and OAI capillaries without NP were 103.6% and 96.8%, 48.5% and 31.5%, and 24.2% and 25.7% for ß2MG and Cys-C, respectively. Furthermore, the method quantitation limit by OAI capillaries was 5 and 10 times lower than that by RAI capillaries and OAI capillaries without NP, respectively. This result indicated that the NP-coated capillaries with OAI are more suitable for using as immunoaffinity in-tube SPME materials than that with RAI.


Assuntos
Anticorpos/química , Nanopartículas/química , Ácidos Polimetacrílicos/química , Microextração em Fase Sólida/instrumentação
9.
Yao Xue Xue Bao ; 48(5): 686-93, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23888691

RESUMO

This study aims to clarify out the anti-inflammatory mechanism of Qingfei Xiaoyan Wan. Chemical constituents of Qingfei Xiaoyan Wan identified by UPLC Q-TOF, were submit to Molinspiration, PharmMapper and KEGG bioinformatics softwares for predicting their absorption parameters, target proteins and related pathways respectively; and the gene chip and real time-PCR were carried out to investigate the expression of inflammatory genes on lung tissue of guinea pigs or human bronchial epithelial cell lines. The predicted results showed that 19 of the 24 absorbable constituents affected at 9 inflammation-related pathways through 11 protein targets; Qingfei Xiaoyan Wan treatment can significantly reduce the infiltration of cytokines through ERK1 gene and 5 inflammatory pathways (Focal adhesion, Fc epsilon RI, Toll-like receptors, NK cell-mediated cytotoxic, and ERK/MAPK). The results of real time-PCR further confirmed that the anti-inflammatory effects of Qingfei Xiaoyan Wan were due to active ingredients such as arctigenin, cholic acid and sinapic acid intervened focal adhesion, Fc epsilon RI signaling and ERK/MAPK pathways. The novel approach of 'drug-target-pathway' will present an effective strategy for the study of traditional Chinese medicines.


Assuntos
Anti-Inflamatórios/farmacologia , Asma/metabolismo , Citocinas/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Inflamação/metabolismo , Animais , Asma/patologia , Linhagem Celular , Ácido Cólico/farmacologia , Ácidos Cumáricos/farmacologia , Combinação de Medicamentos , Células Epiteliais/efeitos dos fármacos , Feminino , Furanos/farmacologia , Cobaias , Humanos , Lignanas/farmacologia , Pulmão/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Distribuição Aleatória , Receptores de IgE/metabolismo , Receptores Toll-Like/metabolismo
10.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m962-3, 2009 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21583408

RESUMO

The Ni(II) atom in the title compound, [Ni(C(12)H(8)N(5))(2)(H(2)O)(4)]·2H(2)O, lies on a center of inversion and is coordinated by the N atoms of two 3,5-di-4-pyridine-1,2,4-triazolate ligands and by four water O atoms in a slightly distorted octa-hedral geometry. The coordinated and uncoordinated water mol-ecules inter-act with the N-heterocycles through O-H⋯N and O-H⋯O hydrogen bonds, generating a three-dimensional supra-molecular architecture.

11.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): m487-8, 2009 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21583739

RESUMO

The Co(II) atom in the title compound, [Co(C(12)H(8)N(5))(2)(H(2)O)(4)]·2H(2)O, lies on a center of inversion and is bonded to two N-heterocycles and to four water mol-ecules in a slightly distorted octahedral coordination. The coordinated and lattice water mol-ecules inter-act with the N-heterocycles through O-H⋯N hydrogen bonds, generating a three-dimensional supra-molecular architecture.

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