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排序方式: 共有458条查询结果,搜索用时 15 毫秒
141.
A Genosensor for Point Mutation Detection of P53 Gene PCR Product Using Magnetic Particles 下载免费PDF全文
Ezat Hamidi‐Asl Jahan Bakhsh Raoof Mohammad Saeid Hejazi Simin Sharifi Seyed Mahdi Golabi Ilaria Palchetti Marco Mascini 《Electroanalysis》2015,27(6):1378-1386
The development of an electrochemical genosensor involving DNA biotinylated capture probe immobilized on streptavidin coated paramagnetic beads and microfluidic based platform for the detection of P53 gene PCR product is reported. The novelty of this work is the combination of a sensitive electrochemical platform and a proper microfluidic system with a simple and effective enzyme signal amplification technology, ELISA, for detection of target DNA sequence and single nucleotide mutation in p53 tumor suppressor gene sequence. The biosensor has been applied to detect the PCR amplified samples and the results shows that it can discriminate successfully perfect matched DNA from mutant form. 相似文献
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Katia Liburdi Raffaello Straniero Ilaria Benucci Anna Maria Vittoria Garzillo Marco Esti 《Applied biochemistry and biotechnology》2012,166(7):1736-1746
In order to use lysozyme as an anti-microbial agent during the winemaking process, hen egg-white lysozyme (LYZ) was covalently
immobilized on two different micro-size magnetic particles (tosyl-activated and carboxylated, TSA and CA, respectively). A
cell suspension of Oenococcus oeni, an oenological strain involved in the winemaking process, was utilized as LYZ substrate. Both a kinetic study and a study
of the stability of free and immobilized LYZ were performed in McIlvane buffer at pH 3.2, that is the average minimum pH value
in wine. The activity and kinetic parameters measured for the free LYZ at pH 3.2 are lower than those reported at the optimum
pH (4.5); however the residual activity at pH 3.2 is sufficient to be of interest for further immobilization and applications
in winemaking. All kinetic parameters of both biocatalysts (LYZ-CA and LYZ-TSA) are altered after immobilization, probably
due to the structural modifications in the active site caused by covalent attachment to the supports. The half-life calculated
at 25 °C was 39 h for free LYZ, while it increased to 280 and 134 h for LYZ-TSA and LYZ-CA, respectively. This result indicates
that immobilization improves the enzyme stability and that LYZ can be utilized in wine applications in its immobilized forms.
In addition, LYZ-TSA seems to be the best biocatalyst for further applications in winemaking. 相似文献
145.
Giorgio Lanzani Rocco Martinazzo Giuliana Materzanini Ilaria Pino Gian Franco Tantardini 《Theoretical chemistry accounts》2007,117(5-6):805-825
Recent years have witnessed an ever growing interest in theoretically studying chemical processes at surfaces. Apart from the interest in catalysis, electrochemistry, hydrogen economy, green chemistry, atmospheric and interstellar chemistry, theoretical understanding of the molecule–surface chemical bonding and of the microscopic dynamics of adsorption and reaction of adsorbates are of fundamental importance for modeling known processes, understanding new experimental data, predicting new phenomena, controlling reaction pathways. In this work, we review the efforts we have made in the last few years in this exciting field. We first consider the energetics and the structural properties of some adsorbates on metal surfaces, as deduced by converged, first-principles, plane-wave calculations within the slab-supercell approach. These studies comprise water adsorption on Ru(0001), a subject of very intense debate in the past few years, and oxygen adsorption on aluminum, the prototypical example of metal passivation. Next, we address dynamical processes at surfaces with classical and quantum methods. Here the main interest is in hydrogen dynamics on metallic and semi-metallic surfaces, because of its importance for hydrogen storage and interstellar chemistry. Hydrogen sticking is studied with classical and quasi-classical means, with particular emphasis on the relaxation of hot–atoms following dissociative chemisorption. Hot atoms dynamics on metal surfaces is investigated in the reverse, hydrogen recombination process and compared to Eley–Rideal dynamics. Finally, Eley–Rideal, collision-induced desorption, and adsorbate-induced trapping are studied quantum mechanically on a graphite surface, and unexpected quantum effects are observed. 相似文献
146.
Ilaria Paolini Maria de la Cruz Pozo-Carrero Francesca Barbetti Zbigniew J. Kaminski Anna M. Papini 《Tetrahedron letters》2007,48(16):2901-2904
Optimization of coupling reactions of glycosylamines with Fmoc-protected aspartic acid, by microwave approach, is described. Different reaction conditions, quantities of substrates and solvents were tested to develop simple and reproducible methodologies. The best results were obtained using new triazine-based coupling reagents with a monomode microwave Discover® BenchMate™ instrument (CEM). The N-glycosyl amino acids were then deprotected to achieve final products for SPPS. 相似文献
147.
Francesco Paolo Invidiata Giancarlo Furn Ilaria Lampronti Daniele Simoni 《Journal of heterocyclic chemistry》1997,34(4):1255-1258
The reaction of thiocarbohydrazide with carboxylic acids at the melting temperature allows an improved preparation of the S-substituted 4-amino-3-mercapto-1,2,4-triazole heterocycles. The crude 4-amino-5-mercapto-1,2,4-triazoles react easily with carboxylic acids or carboxylic acid chlorides to afford the 1,2,4-triazolo[3,4-fc][1,3,4]thiadiazole ring system. 相似文献
148.
Mannelli I Minunni M Tombelli S Wang R Michela Spiriti M Mascini M 《Bioelectrochemistry (Amsterdam, Netherlands)》2005,66(1-2):129-138
An immobilisation procedure based on the direct coupling of thiolated probes (Probe-C6-SH) to bare gold sensor surfaces has been compared with a reference immobilisation method, based on the coupling of biotinylated probes onto a streptavidin-coated dextran-modified surface. The instrumentations used were a quartz crystal microbalance (QCM) and the optical instruments Biacore X and Spreeta based on surface plasmon resonance (SPR). The performances of the DNA-based sensors resulting from direct coupling of thiolated DNA probes onto electrodes of quartz crystals or gold SPR-chips have been studied in terms of the main analytical parameters, i.e. selectivity, sensitivity, reproducibility, etc. In particular, the two immobilisation approaches have been applied to the analysis of oligonucleotides, DNA amplified by polymerase chain reaction (PCR) and genomic DNA enzymatically digested. 相似文献
149.
Ilaria Fragalà 《Journal of Differential Equations》2008,245(5):1299-1322
We consider semilinear elliptic Dirichlet problems in bounded domains, overdetermined with a Neumann condition on a proper part of the boundary. Under different kinds of assumptions, we show that these problems admit a solution only if the domain is a ball. When these assumptions are not fulfilled, we discuss possible counterexamples to symmetry. We also consider Neumann problems overdetermined with a Dirichlet condition on a proper part of the boundary, and the case of partially overdetermined problems on exterior domains. 相似文献
150.
Concentrations of inhalable particulate matter (PM10), Pb, Zn, Pt, Ce, Cd, Se and of Benzo(a)pyrene (BaP) were determined in three locations near Venice from September 2000 to September 2001. Meteorological conditions were considered during the sampling period. All components showed higher concentrations during winter, except for Cd and Se in the two sites at Mestre. Spatial and temporal variations were observed. There were correlations between Pb and Zn and PM10, Cd and Se, Pb and BaP and, in the main street sampling site, also between BaP and Pt. Their possible sources of emission are discussed on the basis of correlations among elements. 相似文献