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271.
A new dual channel micro-electrophoresis system for rapid mutation detection based on heteroduplex analysis was designed and implemented. Mutation detection was successfully achieved in a total separation length of 250 microm in less than 3 min for a 590 bp DNA sample harboring a 3 bp mutation causing an amino acid change. Parylene-C was used as the structural material for fabricating the micro-channels as it provides conformal deposition, transparency, biocompatibility, and low background fluorescence without any surface treatment. A new dual channel architecture was derived from the traditional cross-channel layout by forming two identical channels with independent sample loading and waste reservoirs. The control of injected sample volume was accomplished by a new u-turn injection technique with pull-back method. The use of heteroduplex analysis as a mutation detection method on a cross-linked polyacrylamide medium provided accurate mutation detection in an extremely short length and time. The presence of two channels on the microchip offers the opportunity of comparing the sample to be tested with a desired control sample rapidly, which is very critical for the accuracy and reliability of the mutation analyses, especially for clinical and research purposes. 相似文献
272.
An amperometric biosensor based on horseradish peroxidase (HRP) and carbon nanotube (CNT)/polypyrrole (PPy) nanobiocomposite film on a gold surface has been developed. The HRP was incorporated into the CNT/PPy nanocomposite matrix in one-step electropolymerization process without the aid of cross-linking agent. Amperometric response was measured as a function of concentration of phenol derivatives, at a fixed bias voltage of -50 mV. Optimization of the experimental parameters was performed with regard to pH and concentration of hydrogen peroxide. The linear range, sensitivity and detection limit of the biosensor were investigated for eighteen phenol derivatives. The sensitivity in the linear range increased in this order: 4-methoxyphenol>2-aminophenol>guaiacol=m-cresol>2-chlorophenol=4-chlorophenol=hydroquinone=pyrocatechol>2,6-dimethoxyphenol>3-chlorophenol>p-cresol>p-benzoquinone=4-acetamidophenol>catechol>phenol=pyrogallol=2,4-dimethylphenol. CNTs was shown to enhance the electron transfer as a mediator and capable to carry higher bioactivity owing to its intensified surface area. The biosensor exhibited low detection limits with a short response time (2s) for the tested phenolics compared to the reported working electrodes. It retained 70% of its initial activity after using for 700 measurements in 1 month. 相似文献
273.
In the present work, we synthesized new sulfonamide derivatives with 1,3,4‐oxadiazole moiety and tetrazole ring. The synthesized derivatives of sulfonamides were characterized through Fourier transform infrared, 13C‐APT‐NMR, 1H‐NMR, and high‐resolution liquid chromatography–mass spectrometry. The biological activities of resulting compound were also investigated and observed that the compounds reveal strong antimicrobial activity over some important bacterial strains including Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 13883, and Staphylococcus aureus ATCC 29213. The in vitro antifungal properties of synthesized compounds were also a target using Candida albicans NRRL Y‐477 and Saccharomyces cerevisiae fungal strains. We have provided a useful guideline for future studies about the effect of the chemical structures of sulfonamide compounds on the biological activities. Among the target compounds, 7b , 7c , 7d , and 7e demonstrated surprisingly high antimicrobial activities than did others. 相似文献
274.
275.
Elif Basak Ersoy Nuket Ocal 《Phosphorus, sulfur, and silicon and the related elements》2019,194(3):257-268
1,3-Dipolar cycloaddition reactions were studied to synthesize Polyhedral oligomeric silsesquioxane (POSS)-based norbornyl imide derivatives containing izoxazoline groups in good yields. And also 1,3-dipolar cycloaddition reactions of azomethine ylides with POSS-based norbornene dipolarophiles for a synthesis of the novel POSS-based norbornane-fused spiro-1,3-indandionolylpyrrolidines are reported. All newly synthesized POSS compounds were structurally characterized by FTIR, 1H, 13C NMR, HRMS and GC/MS analyses. 相似文献
276.
Doğan-Sağlamtimur Neslihan Bilgil Ahmet Güven Adnan Ötgün Halime Yıldırım Elif Dilan Arıcan Büşra 《Journal of Thermal Analysis and Calorimetry》2019,135(6):3339-3351
Journal of Thermal Analysis and Calorimetry - Waste tyre and waste polyethylene terephthalate (PET) bottles are major environmental problems. In this study, by using newly designed simple and... 相似文献
277.
Dikici Tuncay Demirci Selim Tünçay Mehmet Masum Yildirim Bercem Kiran Kaya Nusret 《Journal of Sol-Gel Science and Technology》2021,98(3):637-638
Journal of Sol-Gel Science and Technology - 相似文献
278.
279.
Yingjie Zhao Kepeng Chen Dr. Elif Akhuseyin Yildiz Shujing Li Yuqi Hou Xue Zhang Dr. Zhijia Wang Prof. Jianzhang Zhao Dr. Antonio Barbon Prof. Halime Gul Yaglioglu Prof. Huijian Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3591-3599
Intersystem crossing (ISC) was observed for naphthalimide (NI)-derived Tröger's base, and the ISC was confirmed to occur by a spin-orbital charge-transfer (SOCT) mechanism. Conventional electron donor/acceptor dyads showing SOCT-ISC have semirigid linkers. In contrast, the linker between the two chromophores in Tröger's base is rigid and torsion is completely inhibited, which is beneficial for efficient SOCT-ISC. Femtosecond transient absorption (TA) spectra demonstrated charge-separation and charge-recombination-induced ISC processes. Nanosecond TA spectroscopy confirmed the ISC, and the triplet state is long-lived (46 μs, room temperature). The ISC quantum yield is dependent on solvent polarity (8–41 %). The triplet state was studied by pulsed-laser-excited time-resolved EPR spectroscopy, and both the NI-localized triplet state and triplet charge-transfer state were observed, which is in good agreement with the spin-density analysis. The Tröger's base was confirmed to be a potent photodynamic therapy reagent with HeLa cells (EC50=5.0 nm ). 相似文献
280.
Füreya Elif Özbek Mustafa Sertçelik Mustafa Yüksek Betül Küçüköz Ertan Şahin 《Journal of Coordination Chemistry》2019,72(5-7):786-795
Two new complexes, [Co(3-fba)2(na)2(H2O)2] (1) and [Ni(3-fba)2(na)2(H2O)2] (2) (where 3-fba = 3-fluorobenzoate and na?=?pyridine-3-carboxamide, nicotinamide), were synthesized and characterized using different techniques (elemental analysis, FT-IR, UV-Vis spectrophotometer, single-crystal X-ray diffraction, fluorescence spectroscopy, and TGA/DTA analysis). X-ray structural analysis revealed that 1 and 2 are isostructural and exhibit distorted octahedral coordination geometry. In each molecule, metal atoms (Co+2 and Ni+2) are linked by two 3-fluorobenzoate anions, two pyridine-3-carboxamide ligands, and two water molecules per formula unit. The 3-fluorobenzoate and pyridine-3-carboxamide are monodentate through a carboxylate oxygen atom and the nitrogen atom of the pyridine ring, respectively. UV-Vis results showed that the studied complexes have absorption edges similar to semiconductor structures. Namely, 1 and 2 indicated emission behaviors around 370?nm and 361?nm, respectively. 相似文献