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991.
《Electroanalysis》2017,29(12):2832-2838
In this study, a bimetallic nanomaterial‐based electrochemical immunosensor was developed for the detection of carcinoembryonic antigen (CEA) and vascular endothelial growth factor (VEGF) cancer biomarkers at the same time. CEA and VEGF biomarkers are indicators for colon and breast cancers and stomach cancers, respectively. During the study, gold nanoparticle (AuNp), lead nanoparticle (PbNp), copper nanoparticle (CuNp) and magnetic gamma iron(III)oxide (γFe2O3 Np) were synthesized, characterized and used together for the first time in the structure of an electrochemical biosensor based on anti‐CEA and anti‐VEGF. For this purpose, Au SPE based sandwich immunosensor was fabricated by using labeled anti‐CEA (labeled with Pb+2) and labeled anti‐VEGF (labeled with Cu+2). As a result, CEA and VEGF biomarkers were detected following the oxidation peaks of label metals (Pb+2 and Cu+2) by using differential pulse voltammetry. After the experimental parameters were optimized, the linear range was found in the concentration range between 25 ng/mL and 600 ng/mL with the relative standard deviation (RSD) value of (n=3 for 600 ng/mL) 3.33 % and limit of detection (LOD) value of 4.31 ng/mL for CEA biomarker. On the other hand, the linear range was found in the concentration range between 0.2 ng/mL and 12.5 ng/mL with the RSD value of (n=3 for 12.5 ng/mL) 5.31 % and LOD value of 0.014 ng/mL for VEGF biomarker. Lastly, sample application studies for synthetic plasma sample and interference studies with dopamine, ascorbic acid, BSA, cysteine and IgG were carried out. 相似文献
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Neslihan Tekin Kamile Öztürk Talat Baran Barış Kerimoğlu Mehtap Tarhan Ayfer Menteş 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(5):263-270
In the investigation for alternative chemotherapeutic strategies against leukemia, Pd(II) complexes were synthesized and investigated for cytotoxic and apoptotic properties on two human leukemia cell lines (HL-60 and K562). Pd(II) complexes (Pd-5a and Pd-6a) with 5a and 6a as ligands were synthesized and characterized by 1H-NMR and F-TIR. The cytotoxicity of the compounds was quantified using MTT method. Bax, Bcl-2, and caspase 3 gene expression levels were estimated using RT-qPCR. Here we show that Pd(II) complexes have important cytotoxic activity on human leukemia cell lines. RT-qPCR indicated that Bax and caspase 3 gene expression levels were increased after 24 h treatment with Pd-5a and Pd-6a complexes in both HL-60 and K562 cells at some selected dose. Furthermore, Bcl-2 gene expression level decreased after 24 h treatment with Pd-5a and Pd-6a complexes in K562 cells at all selected dose. In HL-60 cells, only one selected Pd-5a dose (25 µM) decreased the gene expression level of Bcl-2. The results obtained in the present investigation indicate that these two newly synthesized Pd(II) complexes have apoptotic effects at appropriate doses through caspase 3 and Bax genes and might represent a novel potentially active agents for the management of human leukemia cell lines. 相似文献
999.
Azido chelating fiber: synthesis,characterization and adsorption performances towards Hg2+ and Pb2+ from water 下载免费PDF全文
Herein, we report the synthesis and adsorption property of a novel chelating fiber containing azido group. Firstly, the brominated fiber (PP‐St‐DVB‐Br) was obtained via the reaction of polypropylene‐(g)‐styrene‐divinylbenzene fiber (PP‐St‐DVB) with bromine in CH2Cl2 solution. Then, azido chelating fiber (PP‐St‐DVB‐N3) was prepared by azidation of PP‐St‐DVB‐Br fiber. Its structure and properties were characterized by Fourier transform infrared, elemental analysis, thermogravimetric analysis, and chemical titration, respectively. The micromophology and functional group distribution in fibrous matrix were investigated by scanning electron microscopy‐energy dispersive spectroscopy. The results show that the chelating fiber has high functional group contents (2.11 mmol/g for PP‐St‐DVB‐N3) and uniform distribution. Different from granulate chelating resin, the novel fibrous adsorbent possesses excellent adsorption ability for Hg(II) and Pb(II) ions (408.9 mg/g for Hg2+ and 334.4 mg/g for Pb2+), and the adsorption capacity of the fiber has no loss until five cycles. The novel absorbent material shows the potential application prospect in the treatment of heavy metal wastewater. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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Lilong Gao Qiang Sun Ying Wang Weipu Zhu Xiaojun Li Qiaojie Luo Xiaodong Li Zhiquan Shen 《先进技术聚合物》2017,28(1):35-40
Water‐soluble poly(ethylene glycol) derivatives with multiple “clickable” mercapto groups or double bonds were facilely synthesized in a large scale by direct polycondensation of oligo(ethylene glycol) diol with mercaptosuccinic acid or maleic acid catalyzed by scandium trifluoromethanesulfonate under mild conditions. Injectable hydrogels containing doxorubicin hydrochloride (DOX · HCl) could be rapidly formed using these poly(ethylene glycol) derivatives as precursors via in situ thiol‐ene “click” reaction under physiological conditions without light, initiator, or metal catalyst. DOX · HCl could be sustained released from the hydrogels as a result of the hindrance of the three dimensional hydrogel network on the drug molecules, which makes this kind of DOX‐loaded hydrogels a promising candidate for localized tumor chemotherapy. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献