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991.
Farzana Ahmad Young Jae Jeon 《International Journal of Polymer Analysis and Characterization》2017,22(8):659-668
In this study, the dye-doped polymer dispersed liquid crystals (PDLC) gratings techniques performed by the various research groups or being developed are briefly reviewed. Especially, the electrically switched diffraction and holographic gratings, have attained much attention by various research groups working in the PDLC-related display studies. The fabrication methodologies used for such grating texture, include like the conventional dye-doped PDLC grating, Azo-dye doped PDLC gratings, and lasing techniques etc., adopted for dye-doped PDLC gratings. The useful features and characteristics of their fabrication process of such gratings are discussed. Finally, some of the future perspectives on this particular research field are presented. 相似文献
992.
《Electroanalysis》2017,29(12):2818-2831
Immobilization of biomolecules with a proper orientation is considered as a basis for diverse biotechnological applications. Herein, we report a host‐guest inclusion complexation between β‐cyclodextrin (β‐CD) and biotin as a versatile approach for the immobilization of biomolecules. As a practical application, a sandwich‐type electrochemical immunosensor was designed for the determination of prostate specific antigen (PSA). The immunosensor was fabricated by in situ electropolymerization of poly(N‐acetylaniline) onto a rGO‐modified Pt electrode. Then, β‐CD was covalently grafted onto the over‐oxidized polymer backbone. For improving the efficiency of the assay, AuNPs were casted on the polymeric film, on the surface of which thionine (TH) as an electron mediator was covalently immobilized. Using a host‐guest inclusion complexation between β‐CD and biotin, a β‐CD/biotin‐Ab1/PSA/Ab2‐horseradish peroxidase (HRP) sandwich was formed on the electrode surface. The analytical signal was produced via electrochemical reduction of THox, generated by biocatalytic oxidation of the THred in the presence of HRP/H2O2. Under optimal conditions, the proposed sensor responded linearly to PSA in the range from 10.0 pg mL−1 to 25.0 ng mL−1, with a low detection limit of 6.7 pg mL−1 (S/N=3). Kinetic parameters of the interaction of β‐CD with Ab1 were also investigated. Finally, the applicability of the immunosensor was successfully investigated for the detection of PSA in human serum samples. 相似文献
993.
《Electroanalysis》2017,29(12):2793-2802
In this work, SiO2/Nb2O5/ZnO prepared by the sol‐gel processing method was used as substrate base for immobilization of the protoporphyrin‐IX ion. Iron(III) ion was inserted into the porphyrin ring (SiNbZn‐PPFe). A simple square wave voltammetry method based on a composite sensor carbon paste electrode of this material,designed as EPC‐SiNbZn‐PPFe, was developed and validated successfully for the determination of L‐tryptophan (Trp). The optimum conditions were obtained by using sensor modified with 18.00 mg SiNbZn‐PPFe material, 12.00 mg graphite powder and 6.0 μL mineral oil and phosphate buffer 0.3 mol L−1 pH 7.0. The sensitivity of the sensor was found to be 0.523 AL mol −1, linear range from 10 to 70 μmol L−1 and limit of detection of 3.28 μmol L−1. Therefore, the developed method was successfully applied for the Trp determination in real samples of pharmaceutical formulation and can be used for routine quality control pharmaceutical formulations containing Trp. 相似文献
994.
《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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