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1.
Anal Chim Acta ; 1178: 338849, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482875

RESUMO

Various mesoporous adsorbents are of great promise for enriching small molecules from biological samples based on the size-exclusion effect. At present, the mesoporous adsorbents have adsorption sites distributed uniformly on the internal and external surfaces of mesopores. However, the adsorption sites on the external surface can adsorb proteins, interfering with the enrichment of small molecules. Herein, a novel immobilized-Ti4+ magnetic mesoporous adsorbent removing the adsorption sites on the external surface was facile prepared via the coupling chemistry of isocyanate with amine and consequent hydrolysis of urea linkage by urease. The adsorbent enables fast and selective enrichment of phosphopeptides and nucleotides from biological samples. In addition, sensitive detection methods for phosphopeptides and nucleotides in human serum are developed by coupling the magnetic solid-phase extraction with matrix-assisted laser desorption/ionization time of flight mass spectrometry and liquid chromatography-mass spectrometer, respectively. Under optimal conditions, response is linear (R2 ≥ 0.9923), limits of detection are low (0.41-9.48 ng mL-1), and reproducibility is acceptable (inter- and intra-day assay RSDs of≤15.0%) for six nucleotides. The developed strategy offers an effective method to eliminate the interference of proteins in the enrichment of small molecules from real biological samples.


Assuntos
Nucleotídeos , Fosfopeptídeos , Adsorção , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
2.
J Colloid Interface Sci ; 586: 683-691, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33223238

RESUMO

As an important biomarker, the analysis of cytochrome c (Cyt c) plays a crucial role in cell-apoptosis or even cancer diagnosis. This work develops a label-free probe for Cyt c using the nitrogen and fluorine co-doped carbon dots (N, F-CDs) which were facile prepared through solvothermal method with 3, 4-difluorophenylhydrazine as precursor. The N, F-CDs have an average diameter of 3.4 nm, and can form a quite stable colloidal solution. The N, F-CDs show bright yellow-green fluorescence, excitation/emission wavelengths 475/530 nm, and a relatively high fluorescence quantum yield of 16.9%. Interestingly, the N, F-CDs indicate a linear and reversible variation of emission intensity with a sensitivity of -1.11% per ℃ in the temperature range from 25 to 60 ℃. Inner filter effect (IFE) between N, F-CDs and Cyt c turns the fluorescence of N, F-CDs from "on" to "off". The sensor possesses the excellent anti-interference ability towards the main components of plasma. Under optimum conditions, there is a linear relationship between fluorescence intensity function (F0-F) and the concentration of Cyt c in the range of 0.5-25 µΜ with a limit of detection (LOD) (S/N = 3) of 0.25 µM. Finally, the developed method has been successfully used to detect Cyt c in human serum sample with satisfactory recoveries in a range of 93.14-110.40%.


Assuntos
Citocromos c , Pontos Quânticos , Carbono , Flúor , Humanos , Nitrogênio , Temperatura
3.
Mikrochim Acta ; 187(8): 472, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32725323

RESUMO

An immobilized metal affinity (IMA) adsorbent was prepared by grafting bottlebrush polymer pendant with iminodiacetic acid (IDA) from the surface of polydopamine (PDA)-coated magnetic graphene oxide (magGO), via surface-initiated atom transfer radical polymerization (SI-ATRP). Poly(hydroxyethyl methacrylate) (PHEMA) was grafted firstly from the PDA-coated magGO as the backbone, and then poly(glycidyl methacrylate) was grafted from the PHEMA chains via the second SI-ATRP to afford the bottlebrush polymer-grafted magGO Thereafter, IDA was anchored on the nanocomposites to produce the IMA adsorbent after chelating copper ions. The adsorbent was characterized by various physical and physicochemical methods. Its adsorption properties were evaluated by using histidine-rich proteins (bovine hemoglobin, BHb) and other proteins (lysozyme and cytochrome-C). The results show that its maximum adsorption capacity to BHb was 378.6 mg g-1, and the adsorption equilibrium can be quickly reached within 1 h. The adsorbent has excellent reproducibility and reusability. It has been applied to selectively purify hemoglobin from human whole blood, indicating its potential in practical applications. Graphical abstract.


Assuntos
Grafite/química , Hemoglobinas/isolamento & purificação , Adsorção , Animais , Bovinos , Cobre/química , Humanos , Iminoácidos/química , Indóis/química , Extração Líquido-Líquido/métodos , Fenômenos Magnéticos , Poli-Hidroxietil Metacrilato/química , Polímeros/química , Ácidos Polimetacrílicos/química , Reprodutibilidade dos Testes
4.
J Pharm Pharmacol ; 72(10): 1370-1382, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32596809

RESUMO

OBJECTIVES: To examine the antiproliferative effects of 1-(4-((5-chloro-4-((2-(isopropylsulfonyl)phenyl)amino)pyrimidin-2-yl)amino)-3-methoxyphenyl)-3-(2-(dimethylamino)ethyl)imidazolidin-2-one (ZX-42) on the echinoderm microtubule-associated protein-4/anaplastic lymphoma kinase fusion gene (EML4-ALK) positive lung cancer cell line H2228 and its underlying mechanism. METHODS: The MTT assay was used to study the effect of ZX-42 on H2228 cell growth. Propidium iodide (PI) staining and Western blotting were used to investigate the cell cycle changes. ZX-42-induced cell apoptosis was determined using the Annexin V-FITC/PI (AV/PI) apoptotic assay kit, acridine orange/ethidium bromide (AO/EB) and Hoechst 33258 staining, Rhodamine 123 (Rh 123) fluorescence assay and Western blotting. ZX-42-induced reactive oxygen species (ROS) production was examined by ROS assay kit. Transmission electron microscope, monodansylcadaverine (MDC) staining and the AV/PI apoptotic assay kit were used to demonstrate the relationship between autophagy and apoptosis. KEY FINDINGS: ZX-42 had good cell viability inhibitory effect on H2228 cells. ZX-42 dramatically inhibited ALK and its downstream pathways. ZX-42 also blocked H2228 cell cycle at G1 phase and then induced apoptosis by activating the mitochondrial pathway. Next, ZX-42 induced the production of ROS, and antioxidant N-acetylcysteine (NAC) reduced ROS production and also decreased apoptotic rates. We also found that ZX-42 induced protective autophagy in H2228 cells. CONCLUSIONS: In summary, ZX-42 is a novel ALK inhibitor that significantly inhibits the cell viability of H2228 cells and ultimately induces apoptosis through the mitochondrial pathway, in which autophagy plays a protective role. Therefore, inhibition of autophagy might enhance the anti-cancer effect of ZX-42.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Células A549 , Quinase do Linfoma Anaplásico/metabolismo , Antineoplásicos/química , Apoptose/fisiologia , Autofagia/fisiologia , Citoproteção/fisiologia , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Inibidores de Proteínas Quinases/química , Estrutura Secundária de Proteína
5.
J Sep Sci ; 43(15): 3110-3119, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32468707

RESUMO

Graphene oxide has received extensive attention because of its unique properties and potential applications. In this study, magnetic nitrogen-doped graphene was prepared by one-step hydrothermal reaction using urea as the dopant and reductant, and ferroferric oxide nanoparticles were in situ deposited on the surface of the nanohybrids. The magnetic nitrogen-doped graphene was characterized using various physical and chemical methods. It was used as a new adsorbent for the magnetic solid-phase extraction of four nonsteroidal anti-inflammatory drugs from the river water. The parameters influencing the extraction efficiency were optimized in detail. Under optimal conditions, this method provided a wide linear range (5-200 ng/mL). The limits of detection were in the range of 1.07-5.10 ng/mL. The recoveries varied from 81.2 to 121.5% with relative standard deviations of less than 10.8%. Overall, we can conclude that the proposed method offers an efficient pretreatment and enrichment and can be successfully applied for the extraction and determination of nonsteroidal anti-inflammatory drugs in complex matrices.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Grafite/química , Nitrogênio/química , Extração em Fase Sólida , Temperatura , Poluentes Químicos da Água/análise , Fenômenos Magnéticos , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
6.
J Sep Sci ; 43(14): 2766-2772, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32419326

RESUMO

Poly(ionic liquid)-modified stationary phases can have multiple interactions with solutes. However, in most stationary phases, separation selectivity is adjusted by changing the poly(ionic liquid) anions. In this work, two poly(ionic liquid)-modified silica stationary phases were prepared by introducing the cyano or tetrazolyl group on the pendant imidazolium cation on the polymer chains. Various analytes were selected to investigate their mechanism of retention in the stationary phases using different mobile phases. Two poly(ionic liquid)-modified stationary phases can provide various interactions toward solutes. Compared to the cyano-functionalized poly(ionic liquid) stationary phase, the tetrazolyl-functionalized poly(ionic liquid) stationary phase provides additional cation-exchange and π-π interactions, resulting in different separation selectivity toward analytes. Finally, applicability of the developed stationary phases was demonstrated by the efficient separation of nonsteroidal anti-inflammatory drugs.

7.
Biochim Biophys Acta Mol Cell Res ; 1867(7): 118712, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32224191

RESUMO

Although anaplastic lymphoma kinase (ALK) inhibitors have good clinical efficacy, the inevitable development of drug resistance is the most common obstacle to their clinical application. There is an urgent need to develop more effective and selective ALK inhibitors to overcome the problem of drug resistance. Here, we screened a series of ALK inhibitors and found that ZX-29 displayed potent cytotoxic activity against ALK rearrangement non-small cell lung cancer (NSCLC) NCI-H2228 cells. Then, we investigated the antitumor effects of ZX-29. We demonstrated that ZX-29 time- and dose-dependently inhibited the viability of NCI-H2228 cells, induced cell cycle arrest in the G1 phase, and then they subsequently progressed into cell death. The type of cell death induced by ZX-29 was apoptosis through endoplasmic reticulum (ER) stress. Interestingly, ZX-29 induced protective autophagy, and inhibiting autophagy could enhance the antitumor effect of ZX-29. Furthermore, ZX-29 suppressed tumor growth in a mouse xenograft model. More importantly, ZX-29 could overcome the drug resistance caused by the ALK G1202R mutation. In conclusion, we demonstrated that ZX-29 showed excellent anti-ALK rearrangement NSCLC activity in vitro and in vivo and overcame the drug resistance caused by an ALK mutation. Therefore, ZX-29 is a promising antitumor drug targeting ALK rearrangement or ALK G1202R mutation NSCLC.


Assuntos
Quinase do Linfoma Anaplásico/genética , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Camundongos , Mutação/genética
8.
Anal Chim Acta ; 1093: 61-74, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735216

RESUMO

Covalent organic frameworks (COFs) have been increasingly employed in separation science, including sample preparation. Herein we fabricated the amino bearing core-shell structured COFs nanospheres [Fe3O4@TpBD(NH2)2], and a novel magnetic boronate affinity adsorbent was synthesized by postsynthetic modification of the Fe3O4@TpBD(NH2)2 with 2-formylphenylboronic acid. The magnetic boronate affinity adsorbent possesses fast magnetic response and high binding capacity up to 1037 µmol g-1 for dopamine. Besides, it was used as an adsorbent for extraction of urinary monoamine neurotransmitters at neutral pH. A method for detection of the monoamine neurotransmitters was developed by coupling the magnetic solid phase extraction with high-performance liquid chromatography-fluorescence detection. Under the optimized conditions, a good analytical method was obtained in the linear dynamic range of 2-200 ng mL-1 with R2 between 0.9917 and 0.9966, with low limit of detection (0.31-0.54 ng mL-1) and limit of quantification (1.04-1.80 ng mL-1). The recoveries of the monoamine neurotransmitters were in the range of 86.3-115%, with relative standard deviations of 2.34-10.5% (intra-day) and 2.84-14.4% (inter-day). The method was successfully applied to the determination of the monoamine neurotransmitters in human urine samples. This work is of great importance for preparing functionalized core-shell structured magnetic covalent organic framework nanospheres, it also demonstrates the feasibility of the functionalized magnetic COFs as adsorbents in sample pretreatment.


Assuntos
Monoaminas Biogênicas/urina , Ácidos Borônicos/química , Catecolaminas/urina , Estruturas Metalorgânicas/química , Nanosferas/química , Neurotransmissores/urina , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/síntese química , Porosidade , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos
9.
Se Pu ; 38(4): 424-429, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-34213224

RESUMO

A novel mixed-mode chromatographic stationary phase was prepared via surface initiated atom transfer radical polymerization using an imidazole side-group functionalized ionic liquid monomer, 1-(4-vinylbenzyl)-3-cyanomethyl bromide. The structure of the stationary phase was characterized by infrared spectroscopy, elemental analysis, and thermogravimetric analysis. The stationary phase showed good separation ability. The retention mechanism of reversed-phase/ion exchange toward solutes on the stationary phase was verified by determining the effect of mobile phase pH on the retention of substances. Compared with octadecylsilyl-bonded silica stationary phase, it is confirmed that the poly(ionic liquid)-modified stationary phase provides π-π interaction toward the retention of the solutes. The results show that the functionalization of imidazole side groups is a feasible method for preparing new ionic liquid stationary phases.

10.
Toxicol Appl Pharmacol ; 383: 114781, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618659

RESUMO

In recent years, anaplastic lymphoma kinase (ALK) rearrangement-positive anaplastic large cell lymphoma (ALCL) has rising morbidity and mortality. Unfortunately, no ALK inhibitor has been approved by the FDA for single treatment of ALK rearrangement-positive ALCL. In this study, we investigated the antitumor effect of ZYY, a novel ALK inhibitor, showing a strong growth inhibitory effect on Karpas299 cells in vitro and in vivo. Specifically, ZYY significantly reduced the mRNA and protein expression of ALK and its downstream signaling proteins in Karpas299 cells. Furthermore, ZYY induced G1 phase arrest and promoted apoptosis in Karpas299 cells. Furthermore, we demonstrated that ZYY-induced apoptosis was mainly related to the mitochondria-dependent endogenous pathway. In vitro studies further showed that ZYY induced autophagy in Karpas299 cells, along with increased levels of the autophagy-related proteins, including LC3II and Beclin-1. Moreover, knockdown Beclin-1 and application of autophagy inhibitor chloroquine potentiated ZYY-induced cytotoxicity and apoptosis in vitro, indicating that cytoprotective autophagy might be triggered by ZYY in Karpas299 cells. Taken together, the novel ALK inhibitor ZYY has tremendous potential for treating human ALCL, and a combination of autophagy and ALK inhibition could effectively elicit potent antitumor effects.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores do Crescimento/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Células A549 , Quinase do Linfoma Anaplásico/metabolismo , Animais , Antineoplásicos/química , Autofagia/fisiologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Feminino , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
11.
J Sep Sci ; 42(23): 3512-3520, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31556204

RESUMO

In this work, core-shell structured magnetic mesoporous carbon nanospheres were fabricated from the carbonization of metal-polyphenol coordination polymer-coated Fe3 O4 nanoparticles. The preparation method is simple, fast, versatile, and easy to scale up. Magnetic mesoporous carbon nanospheres exhibit a high specific surface area, high superparamagnetism, and high adsorption efficiencies for phthalates. Four phthalates were extracted from aqueous solutions by using magnetic mesoporous carbon nanospheres via magnetic solid phase extraction. Subsequent analysis was performed by using high-performance liquid chromatography with ultraviolet detection. The analytical method has good linearity in the concentration range of 1-200 ng/mL for diethyl phthalate, diisobutyl phthalate, and dicyclohexyl phthalate, and 3-200 ng/mL for dipropyl phthalate. The limits of detection were in the range of 0.10-0.62 ng/mL. Compared with previous methods, this method has a lower detection limit, wider linearity range, and faster adsorption and desorption rates. The results indicate that magnetic mesoporous carbon nanospheres are suitable for the enrichment of hydrophobic substances from aqueous solutions.

12.
Macromol Rapid Commun ; 40(22): e1900441, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31553508

RESUMO

Finely tuning the photodegradation behavior of the layer-by-layer (LbL) film from the view of controlling the chemical structure of the film-building polymer is still a challenge in related fields. To meet this requirement, a photodegradable polymer (P1) is rationally designed for assembling a visible-light-degradable multilayer film with polystyrene sulfonate (PSS). Compared with similar photopolymers (P2 and P3), this asymmetric picolinium-containing polymer can significantly enhance the degradation rate of as-prepared LbL films; under the same degradation condition, the degradation rate of (P1/PSS)10 is 3 and 6.6 times that of (P2/PSS)10 and (P3/PSS)10, respectively. Moreover, near-infrared light (NIR) is available for triggering the degradation of this film with the assistance of upconversion nanoparticles of YbTm@Lu. The cell cytotoxicity and cell proliferation experiments reveal that P1 is nontoxic and favorable for cell proliferation at concentrations of up to 500 µg mL-1 . As for (PSS/P1)10 films, the ratio of cell number of these two samples ((PSS/P1)10 modified: photodegraded) increases dramatically and reaches about 1.67:1 after 72 h incubation. On the basis of these results, it is anticipated that P1 and this LbL film is an exceptional candidate for visible-light/NIR degradable materials in materials and biological science, medicine, and optics.


Assuntos
Materiais Biocompatíveis/química , Ácidos Picolínicos/química , Polieletrólitos/química , Polímeros/química , Adulto , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células Cultivadas , Humanos , Raios Infravermelhos , Membranas Artificiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Modelos Químicos , Estrutura Molecular , Polimerização/efeitos dos fármacos , Polimerização/efeitos da radiação , Polímeros/síntese química
13.
J Chromatogr A ; 1607: 460401, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31376983

RESUMO

Boronate affinity is an important method for the enrichment and separation of cis-diol containing compounds, but most of the conventional boronate materials suffer from weak binding strength as well as low binding capacity towards glycoproteins due to the use of single boronic acids as ligands. In this work, a novel multidentate boronate magnetic adsorbent was assembled by using amined polyhedral oligomeric silsesquioxane as spacer and a diboronic acid as ligand. The specially designed adsorbent exhibited high adsorption capacity for cis-diols due to the high density of phenylbronic acid moieties. More interestingly, the dissociation constants toward glycoproteins on the material were lowered to be ∼10-6 M, being at least 3 orders lower than the single boronic acid bonded adsorbents. By comparing the binding properties of small molecules containing one and two pairs of cis-diols, the enhanced binding strength of glycoproteins on the multidentate boronate magnetic adsorbent was attributed to the synergistic binding of glycoproteins on the special interface. The new materials successfully captured glycoproteins from 1000-fold diluted egg white, suggesting that the material could be an optional alternative adsorbent for enriching trace glycoproteins from complex bio-samples.


Assuntos
Ácidos Borônicos/química , Glicoproteínas/química , Fenômenos Magnéticos , Compostos de Organossilício/química , Adenosina/análise , Adsorção , Animais , Galinhas , Cinamatos/análise , Depsídeos/análise , Cinética , Ligantes , Temperatura
14.
Talanta ; 195: 381-389, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30625558

RESUMO

A metal affinity-carboxymethyl cellulose functionalized magnetic graphene, namely MGCI-Cu composite, was prepared by successive modifications of graphene oxide nanosheets with magnetic nanoparticles, carboxymethyl cellulose (CMC), iminodiacetic acid (IDA) and then chelated with copper ions. The successful modifications of the graphene surface were demonstrated by various characterizations, and a high density of 6.17 µmol m-2 for metal affinity groups was obtained. The composite exhibited high adsorption selectivity toward histidine-rich proteins. The adsorption was governed by strong metal affinity binding force between hisitidine residues of proteins and immobilized Cu2+ ions of MGCI-Cu composite. In particular, highly selective isolation of hemoglobin (Hb) was achieved in 0.2 mol L-1 phosphate buffer at pH 8. The adsorption capacity of Hb significantly increased to 769 mg g-1 in comparison to that of 435 mg g-1 on metal affinity modified magnetic graphene composite (MGI-Cu) without CMC modification. The adsorbed Hb molecules were recovered with a carbonate buffer (0.2 mol L-1 pH 10) containing 0.5 mol L-1 imidazole. MGCI-Cu composite displayed favorable reusability for at least four times after regeneration of the composite by edetic acid (EDTA) and Cu2+ solution. The practical applications demonstrated that MGCI-Cu composite could highly selectively isolate Hb from human whole blood and polyhistidine-tagged recombinant protein from Escherichia coli (E. coli) lysate.


Assuntos
Carboximetilcelulose Sódica/química , Cobre/química , Grafite/química , Iminoácidos/química , Nanopartículas de Magnetita/química , Proteínas/química , Adsorção , Escherichia coli , Hemoglobinas/química , Humanos , Muramidase/química , Mioglobina/química , Proteínas Recombinantes/química , Soroalbumina Bovina/química
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1097-1098: 18-26, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30196240

RESUMO

The modification with high-density functional groups is a widely used method to enhance the binding capacity of membrane adsorbers, where the types of the attached groups are crucial to achieve good selectivity for protein separation. In this work, a novel tetrazole-functionalized weak cation-exchange membrane with high-capacity was prepared by constructing tetrazole-containing polymer brushes on the surface of regenerated cellulose membrane via the combination of surface-initiated atom transfer radical polymerization (SI-ATRP) and "click chemistry" between cyano and azide. Densities of tetrazolyl groups on the membranes can be easily controlled by manipulating the polymerization time. The binding capacity of lysozyme increased with the polymerization time but eventually reached maximum due to the reduction of the utilization percentage of ion-exchange sites. The adsorption of newly designed membrane conforms to the feature of weak cation exchanger in terms of pH and salt effects, whereas the effect of pH exhibits a large difference from that on the carboxylic-functionalized ion-exchange membranes. Most importantly, the membranes possess higher dynamic binding capacity independent of the flow rate of mobile phase compared with the previously reported cation-exchange membranes. Featured with the unique properties, the modified membrane could simultaneously purify lysozyme and ovotransferrin from hen egg white at higher productivity. The present work provides a new alternative for membrane chromatography of biomacromolecules.


Assuntos
Cromatografia por Troca Iônica/métodos , Proteínas Recombinantes/isolamento & purificação , Tetrazóis/química , Concentração de Íons de Hidrogênio , Modelos Químicos , Muramidase , Polimerização , Proteínas Recombinantes/análise , Proteínas Recombinantes/química
16.
Mikrochim Acta ; 185(8): 361, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29978437

RESUMO

The authors report on the preparation of composites made from graphene oxide (GO) and zeolitic imidazolate framework-8 (ZIF-GO), with various fractions of GO. GO acts as the template and as a modulator for the surface properties of the composites. It also improves the selective adsorption of specific proteins, i.e. hemoglobin (Hb) in this case. The adsorption capacity for Hb is as high as 436 mg g-1 when using a composite containing 20% of GO as sorbent, and 95% of specific activity is maintained for the Hb recovered. The sorbent is applied to selectively isolate Hb from human whole blood. Graphical abstract Graphene oxide-zeolitic imidazolate framework-8 composites (ZIF-GO) with varying mass ratios of GO were prepared in order to tune surface properties and to improve the adsorption selectivity toward hemoglobin.


Assuntos
Fracionamento Químico/métodos , Grafite/química , Hemoglobinas/isolamento & purificação , Imidazóis/química , Óxidos/química , Zeolitas/química , Adsorção , Hemoglobinas/análise , Humanos , Modelos Moleculares , Conformação Molecular
17.
Mikrochim Acta ; 185(8): 370, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29987393

RESUMO

Poly(2-naphthyl acrylate) was first grafted onto silica-coated magnetic nanoparticles by surface-initiated atom transfer radical polymerization to prepare a reversed-phase magnetic adsorbent. The resulting polymer brush displays enhanced extraction efficiency by offering active sites on the surfaces of adsorbent. It was applied to the preconcentration of the non-steroidal antiinflammatory drugs (NSAIDs) indomethacin (InDo) and diclofenac (DIC). These drugs interact with the sorbent through hydrophobic and π-interactions, and via electrostatic attraction. By coupling the magnetic solid-phase extraction with HPLC, a method for analysis of InDo and DIC in the environmental water samples was established. The limits of detection range from 0.62 to 0.64 ng·mL-1, and the relative standard deviations for intra-and inter-day analyses of spiked water samples are <11.9%, and relative recoveries are between 62.1 and 96.7%. Graphical abstract A reversed-phase magnetic adsorbent was prepared by grafting poly(2-naphthyl acrylate) brush on the surface of silica coated magnetic nanoparticles. Due to the two conjugated aromatic rings of the monomer, the polymer brush can effectively extract non-steroidal anti-inflammatory drugs through strong π- and hydrophobic interactions.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Anti-Inflamatórios não Esteroides/análise , Diclofenaco/análise , Indometacina/análise , Nanopartículas de Magnetita/química , Naftalenos/química , Polímeros/química , Adsorção , Anti-Inflamatórios não Esteroides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Diclofenaco/isolamento & purificação , Indometacina/isolamento & purificação , Dióxido de Silício/química , Extração em Fase Sólida
18.
Talanta ; 185: 89-97, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29759254

RESUMO

Ionic liquids (ILs) immobilized on silica as a novel high-performance liquid chromatography (HPLC) stationary phase have attracted considerable attentions. However, it has not been applied to protein separation. In this paper, N-methylimidazolium IL-modified silica-based stationary phase (SilprMim) was prepared and investigated as a novel multi-interaction stationary phase with positive charges for protein separation. The results indicate that all of the basic proteins tested cannot be adsorbed on this novel stationary phase, whereas all of the acidic proteins tested can be retained, and the baseline separation of eight kinds of acidic protein standards can be achieved when being performed under reversed phase/ion-exchange chromatography (RPLC/IEC) mode. Compared with commonly used commercial C4 column, the novel stationary phase can show good selectivity and resolution to acidic proteins. The effects of acetonitrile and salt concentration, pH as well as the ligand structure on protein separation were investigated in detail. In addition, the mix-mode retention mechanism of proteins on the SilprMim column was also discussed using stoichiometric displacement theory for retention in LC (SDT-R). The result shows that the protein retention can be controlled mainly by the electrostatic and hydrophobic interactions between the proteins and the stationary phase. As a result, with such characteristics of multi-interaction mechanism and multi-modal separation, not only the selectivity to the acidic proteins can be enhanced, but also a better resolution can be achieved. The result demonstrates that the SilprMim mixed-mode chromatography (MMC) column has a promising application in the separation and analysis of acidic proteins from the complex samples.


Assuntos
Imidazóis/química , Líquidos Iônicos/química , Proteínas/isolamento & purificação , Dióxido de Silício/química , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Concentração de Íons de Hidrogênio , Estrutura Molecular , Proteínas/química
19.
Mikrochim Acta ; 185(2): 113, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29594664

RESUMO

The authors describe the preparation of copper-doped magnetic microspheres (Cu-Fe3O4) by a solvothermal method. Due to their good magnetic property and high affinity for compounds containing an imidazole moiety (containing N-H), they are excellent adsorbents for such compounds as tested by eighteen compounds. Specifically, a method has been developed for magnetic solid-phase extraction (MSPE) of theophylline (TP) from plasma. The method enables selective enrichment of TP over many potential interferents that can occur in plasma. Following elution with alkaline methanol, TP was quantified by HPLC-UV at a detection wavelength of 272 nm. Under the optimized conditions, a linear response is found for the 0.02 to 20 µg·mL-1 concentration range, and the limit of detection is as low as 3 ng·mL-1. Recoveries from spiked samples range from 91.2 to 100.4%, and the repeatabilities are between 2.9 and 12% (for n = 6). The method was successfully applied to the determination of TP in rabbit and rat plasma. Graphical abstract Copper-doped magnetic microspheres are described that show good magnetic property and high affinity for compounds containing an imidazole moiety (containing an N-H group). They were successfully applied to the selective extraction of theophylline in plasma.

20.
Chem Biol Interact ; 284: 24-31, 2018 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-29458018

RESUMO

Anaplastic lymphoma kinase (ALK)-positive cancers have rising morbidity and mortality in recent years, and novel chemotherapeutic drugs with no drug resistance and high activity for treating ALK-positive cancers are needed urgently. In this study, we investigated the anti-cancer effect of 5-chloro-N4-(2-(isopropylsulfonyl)phenyl)-N2-(2-methoxy-4-(4-((4-methylpiperazin-1-yl)methyl)-1H-1,2,3-triazol-1-yl)phenyl)pyrimidine-2,4-diamine (WY-135), a novel ALK inhibitor, on nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) positive cancer cell line Karpas299 and echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) positive cancer cell line H2228. In vitro enzyme assay showed that WY-135 had better enzyme inhibitory activity than ceritinib. MTT assay showed that WY-135 had similar inhibitory activity with ceritinib in Karpas299 and H2228 cells. The cell cycle analysis proved that WY-135 induced cell cycle arrest at G1 phase in a dose-dependent manner and subsequently progressed into apoptosis. Real-time PCR analysis revealed that the mRNA level of ALK was significantly reduced in Karpas299 and H2228 cells treatment with WY-135. Furthermore, western blot analysis showed that WY-135 significantly suppressed ALK and its downstream protein expression. Taken together, WY-135 exhibits significant anti-cancer activity through inhibiting ALK and its downstream protein expression, arresting cell cycle and eventually inducing cell apoptosis in Karpas299 and H2228 cells. WY-135 is a promising ALK inhibitor with novel structure that has tremendous potentials for therapeutic treatment of NPM-ALK or EML4-ALK positive cancers.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/química , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Triazóis/química , Quinase do Linfoma Anaplásico , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/química , Estrutura Terciária de Proteína , Pirimidinas/farmacologia , Pirimidinas/toxicidade , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Sulfonas/química , Sulfonas/farmacologia , Triazóis/toxicidade
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