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71.
Bioactive modification of silicon surface using self-assembled hydrophobins from Pleurotus ostreatus
L. De Stefano I. Rea E. De Tommasi I. Rendina L. Rotiroti M. Giocondo S. Longobardi A. Armenante P. Giardina 《The European physical journal. E, Soft matter》2009,30(2):181-185
A crystalline silicon surface can be made biocompatible and chemically stable by a self-assembled biofilm of proteins, the
hydrophobins (HFBs) purified from the fungus Pleurotus ostreatus. The protein-modified silicon surface shows an improvement in wettability and is suitable for immobilization of other proteins.
Two different proteins were successfully immobilized on the HFBs-coated chips: the bovine serum albumin and an enzyme, a laccase,
which retains its catalytic activity even when bound on the chip. Variable-angle spectroscopic ellipsometry (VASE), water
contact angle (WCA), and fluorescence measurements demonstrated that the proposed approach in silicon surface bioactivation
is a feasible strategy for the fabrication of a new class of hybrid devices. 相似文献
72.
Thorbjrn B. Nielsen Rasmus P. Thomsen Michael R. Mortensen Jrgen Kjems Per Franklin Nielsen Thomas E. Nielsen Anne Louise B. Kodal Emiliano Cl Kurt V. Gothelf 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(27):9166-9170
The development of methods for conjugation of DNA to proteins is of high relevance for the integration of protein function and DNA structures. Here, we demonstrate that protein‐binding peptides can direct a DNA‐templated reaction, selectively furnishing DNA–protein conjugates with one DNA label. Quantitative conversion of oligonucleotides is achieved at low stoichiometries and the reaction can be performed in complex biological matrixes, such as cell lysates. Further, we have used a star‐like pentameric DNA nanostructure to assemble five DNA–Rituximab conjugates, made by our reported method, into a pseudo‐IgM antibody structure that was subsequently characterized by negative‐stain transmission electron microscopy (nsTEM) analysis. 相似文献
73.
Morganti A Becagli S Castellano E Severi M Traversi R Udisti R 《Analytica chimica acta》2007,603(2):190-198
A method was developed for the quantitative determination of cations and anions in Antarctic ice cores at μg L−1 and sub-μg L−1 levels by ion chromatography (IC), after ultra-clean decontamination procedures. Strict manipulation and decontamination procedures were used in sub-sampling, in order to minimise sample contamination. Na+, NH4+, K+, Mg2+ and Ca2+ were determined by 12-min isocratic elution (H2SO4 eluent). Contemporaneously, in a parallel device, F−, MSA (methanesulfonic acid), Cl−, NO3− and SO42− were analysed in a single 12-min run with multiple-step elution using Na2CO3/NaHCO3 as eluent. Melted ice samples were pumped from their still-closed containers (polystyrene accuvettes with polyethylene caps), shared between the two ion chromatographic systems, online filtered (0.45 μm Teflon membrane) and pre-concentrated (anions and cations pre-concentration columns) using a flow analysis system, thus avoiding uptake of contaminants from the laboratory atmosphere. Sensitivity, linear range, reproducibility and detection limit were evaluated for each chemical species. Anion or cation detection limits ranged from 0.01 to 0.15 μg L−1 by using a relatively small sample volume (1.5 mL). Such values are significantly lower than those reported in literature for almost all the components. These methods were successfully applied to the analysis of cations and anions at trace levels in the Dome C ice core. The composition of the atmospheric aerosol for the last 850 kyr was reconstructed by high-resolution continuous chemical stratigraphies. Concentration trends in the last nine glacial-interglacial climatic cycles were shown and briefly discussed. 相似文献
74.
D. O. Eremenko V. A. Drozdov S. Yu. Platonov O. V. Fotina O. A. Yuminov G. Giardina G. Mandaglio M. Manganaro 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(4):509-512
A dynamic model of the mass-angular correlations of quasi-fission fragments was developed. The projection of the angular momentum
onto the symmetry axis of the dinuclear system and its rotation angle are treated as dynamic variables in the model. The model
was tested in the analysis of the experimental data for the 64Ni + 198Au reaction at E
lab = 383 and 418 MeV. Information on lifetimes of the dinuclear system was obtained. 相似文献
75.
A green alternative method for analysis of ivermectin and moxidectin in environmental water samples using automatized preconcentration previous MEEKC 下载免费PDF全文
Emiliano Felici Cristian Casado Chien C. Wang Julio Raba María R. Gomez 《Electrophoresis》2016,37(22):2977-2985
Antiparasitic drugs derived from macrocyclic lactones (MLs) are widely used in livestock activities around the world. An increasing concern for local authorities is the environmental pollution as a consequence of veterinary drugs widely used in rural areas. The purpose of environmental analysis is to monitor low levels of pollutant analytes in a large number of samples. Also, due to the lipophilic characteristic of these lactones, long‐chain solvents are usually required for performing sample treatment before and during the analysis. Therefore, sensitive, specific, robust, and environmentally friendly analytical methods are still required. In this paper, a new automatized preconcentration methodology followed by microemulsion electrokinetic chromatography analysis was developed for the simultaneous separation and determination of the most used MLs, ivermectin (IVM) and moxidectin (MXD) in environmental water. XAD‐4 resin was employed as an adsorbent for the preconcentration process and ethanol was used as the eluent. In contrast to traditional analysis for IVM and MXD, in this methodology nonpolluting solvents were involved during the whole process and therefore, it could be considered as a contribution to green analytical chemistry. Under optimal experimental conditions, LOD obtained for IVM and MXD were of 3 × 10?3 and 3.6 × 10?3 μg/L, respectively. 相似文献
76.
Ombretta Largiuni Emiliano Castellano Alessio Migliori Rita Traversi Giovanni Piccardi Roberto Udisti 《International journal of environmental analytical chemistry》2013,93(6-7):537-549
Formaldehyde concentrations were determined in over 1800 snow samples (snowpit, firn cores and superficial snow) from Antarctica by a sensitive spectrofluorimetric Flow Injection Analysis method. The method performances (detection limit: 55?ng/L; reproducibility: 2.5% at 1?µg/L level; linear range: 0.1–3000?µg/L) allowed a reliable determination of formaldehyde content in all the collected samples. The range of determined concentrations was 0–70?µg/L with a mean concentration of 7.7?µg/L and a median concentration of 5.8?µg/L. The formaldehyde background level was estimated at a few micrograms per liter in coastal and plateau areas of Northern Victoria Land. In some stations the background values are modulated by HCHO deposition events recurring over relatively large time periods. 相似文献
77.
78.
A.K. Nasirov G. Mandaglio M. Manganaro A.I. Muminov G. Fazio G. Giardina 《Physics letters. [Part B]》2010
The role of the entrance channel has been studied to ascertain a cause of the observed difference between the evaporation residue cross sections normalized to the fusion cross sections in the 19F + 181Ta and 16O + 184W reactions at high excitation energies. The theoretical analysis performed in the framework of the dinuclear system and advanced statistical models showed that the more intense yield of evaporation residues in the 16O + 184W reaction in comparison with that in the 19F + 181Ta reaction was explained by the large capture and fusion cross sections in the former reaction, which is in agreement with the experimental data. The observed decrease in the evaporation residue cross section normalized to the fusion cross section in the 19F + 181Ta reaction, in comparison with one in the 16O + 184W reaction at large excitation energies, is caused by the unintentional inclusion of the quasifission and fast fission contributions in the fissionlike fragment yields that were used in reconstructing the experimental fusion cross section in the normalizing procedure. The range of the angular momentum distribution for both systems was similar, but the partial cross sections are different, showing the presence of a difference in the hindrance to complete fusion in both reactions. 相似文献
79.
We present experimental results of enhanced second- and third-harmonic generation efficiency from Fresnel-lensing effects. We obtained enhancement by a factor of 6 in the third-harmonic yield by simply limiting the laser beam with an iris. Higher enhancement factors (up to 16) were obtained with a Fresnel zone plate. The experimental findings are in good agreement with the results of a simple theoretical analysis. 相似文献
80.
Cabras T Inzitari R Fanali C Scarano E Patamia M Sanna MT Pisano E Giardina B Castagnola M Messana I 《Journal of separation science》2006,29(17):2600-2608
In the present study the analytical potential of HPLC-MS/MS was utilized for the structural characterization of a post-translational modification of statherin. Human salivary statherin (M(av)5380.0 +/- 0.3 Da) is transformed by the action of transglutaminase 2 into a cyclic derivative with an average molecular mass of 5363.0 +/- 0.3 Da. The intra-molecular bridge is generated by the loss of an ammonia molecule between the unique Ione-pair donating nucleophile Lys-6 and one acceptor among the seven glutamine residues of statherin. Digestion of the cyclic derivative with chymotrypsin, proteinase K, and carboxypeptidase Y, monitored by HPLC-electrospray ionization-ion trap-mass spectrometric analysis, demonstrated that cyclization involved almost specifically Gln-37 (> 95%), with the percentage of Gln-39 implicated in the cross-linkiing being less than 5%. The main derivative was named cyclostatherin Q37. Guineapig transglutaminase 2 showed high affinity for statherin in vitro (Km = 0.65 +/- 0.06 microM). Cyclo-statherin was detected in vivo by HPLC-electrospray ionization ion trap-mass spectrometry analysis of whole human saliva and it accounted for about 1% of total statherin. Detection of cyclo-statherin in whole saliva is suggestive of a putative role of this molecule in the formation of the "oral protein pellicle". 相似文献