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Ramona Abbattista Ilario Losito Cristina De Ceglie Graziana Basile Cosima D. Calvano Francesco Palmisano Tommaso R.I. Cataldi 《Journal of mass spectrometry : JMS》2019,54(10):843-855
A systematic structural characterization of the isomeric forms related to ligstroside aglycone (LA), one of the most relevant secoiridoids contained in virgin olive oils, was performed using reverse phase liquid chromatography with electrospray ionization Fourier‐transform single and tandem mass spectrometry, operated in negative ion mode (RPLC‐ESI(?)‐FTMS and FTMS/MS). The high mass resolution and accuracy provided by the adopted orbital trap mass analyzer enabled the recognition of more than 10 different isomeric forms of LA in virgin olive oil extracts. They were related to four different types of molecular structure, two of which including a dihydropyranic ring bearing one or two aldehydic groups, whereas the others corresponded to dialdehydic open‐structure forms, differing just for the position of a C═C bond. The contemporary presence of enolic or dienolic tautomers associated to most of these compounds, stable at room temperature (23°C), was also assessed through RPLC‐ESI‐FTMS analyses operated under H/D exchange conditions, ie, by using D2O instead of H2O as co‐solvent of acetonitrile in the RPLC mobile phase. As discussed in the paper, the results obtained for LA indicated a remarkable structural similarity with oleuropein aglycone (OA), the most abundant secoiridoid of olive oil, whose isoforms had been previously characterized using the same analytical approach. 相似文献
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Emily Bulukin Graziana Bagni Grete Jonsson Thierry Baussant 《International journal of environmental analytical chemistry》2013,93(14):1039-1048
This article deals with the development and novel application of an amperometric peroxidase biosensor for monitoring fish exposure to petroleum-related discharges, in particular, to alkyl phenols (AP) using fish bile as the main sample material. The biosensor consisted of a screen-printed electrode coupled with peroxidase immobilized by glutaraldehyde cross-linking. The sensor was optimized with regards to factors such as immobilization procedures, substrate selectivity, and matrix effects. The biosensor was used for the analysis of fish bile samples from Atlantic cod (Gadus morhua L.) exposed in the laboratory during a 2 week period to different petroleum related compounds. The biosensor could distinguish between bile samples of fish exposed to water containing high concentrations (a mixture of C4–C7) to moderate levels (mainly C0–C5) of alkylphenols and that of the control group. 相似文献
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Francesco Altomare Sabina Milella Graziana Musceo 《Journal of Evolution Equations》2011,11(4):771-792
Of concern are multiplicative perturbations of the Laplacian acting on weighted spaces of continuous functions on
\mathbbRN, N 3 1{{\mathbb{R}}^{N},\; N\geq1} . It is proved that such differential operators, defined on their maximal domains, are pre-generators of positive quasicontractive
C
0-semigroups of operators that fulfill the Feller property. Accordingly, these semigroups are associated with a suitable probability
transition function and hence with a Markov process on
\mathbbRN{{\mathbb{R}}^{N}} . An approximation formula for these semigroups is also stated in terms of iterates of integral operators that generalize
the classical Gauss-Weierstrass operators. Some applications of such approximation formula are finally shown concerning both
the semigroups and the associated Markov processes. 相似文献
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Ciofani G Genchi GG Liakos I Athanassiou A Dinucci D Chiellini F Mattoli V 《Journal of colloid and interface science》2012,374(1):308-314
A novel and simple method for the preparation of chemically functionalized boron nitride nanotubes (BNNTs) is presented. Thanks to a strong oxidation followed by the silanization of the surface through 3-aminopropyl-triethoxysilane (APTES), BNNTs exposing amino groups on their surface were successfully obtained. The efficacy of the procedure was assessed with EDS and XPS analyses, which demonstrated a successful functionalization of ~15% boron sites. This approach opens interesting perspectives for further modification of BNNTs with several kinds of molecules. Since, in particular, biomedical applications are envisaged, we also demonstrated in vitro biocompatibility and cellular up-take of the functionalized BNNTs. 相似文献
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Hyaluronic Acid Nanoporous Microparticles with Long In Vivo Joint Residence Time and Sustained Release 下载免费PDF全文
Graziana Palmieri Antonio Rinaldi Luisa Campagnolo Mariarosaria Tortora Maria Federica Caso Maurizio Mattei Andrea Notargiacomo Nicola Rosato Massimo Bottini Francesca Cavalieri 《Particle & Particle Systems Characterization》2017,34(6)
A simple approach is reported to engineer biodegradable and biocompatible nanoporous hyaluronic acid particles (NPHAs) with a characteristic sponge‐like morphology and uniform size. These NPHAs can be synthesized using the concomitant cross‐linking of hyaluronic acid and the cross‐linking agent precipitation. The nanoporous architecture of NPHAs prevents the rapid enzymatic degradation of hyaluronic acid and controls the erosion of microparticles in physiological conditions. Once injected into an intra‐articular body cavity of healthy mice, these NPHAs reside at the point‐of‐delivery for an extended time period, exhibiting a sustained release of hyaluronic acid. In addition, in vivo studies indicate the persistence of NPHAs in the knee joints with neither accumulation into major organs, nor any local or systemic side‐effect. The use of NPHAs is emphasized as reservoirs of hyaluronic acid, effectively providing an innovative and safe platform for prolonging the favorable effects displayed by hyaluronic acid on joints affected by osteoarthritis. 相似文献
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