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11.
Francesco Barbato Maria Immacolata La Rotonda Agnese Miro Patrizia Morrica Fabiana Quaglia 《Journal of inclusion phenomena and macrocyclic chemistry》2000,38(1-4):423-433
This study was carried out with the aim ofinvestigating the interactions between-cyclodextrin and carbaryl, a carbamatepesticide, and their effect on some physico-chemicalproperties of carbaryl, such as aqueous solubility andlipophilicity. The interactions between carbaryl and-cyclodextrin were thoroughly investigated bothin solution and in the solid state. The effect of-cyclodextrin on the aqueous solubility ofcarbaryl was evaluated by the phase solubility method.The amount of carbaryl dissolved increased linearlywith the addition of -cyclodextrin according toan AL type plot and without precipitation of thecomplex. The apparent stability constant of thecomplex was 289 ± 21 M-1, assuming a 1 : 1stoichiometry; this value was confirmed by a methodbased on circular dichroism measurements.Equimolar carbaryl/-cyclodextrin solid systemswere prepared by physical-mixing and freeze-drying,and fully characterised by Differential ScanningCalorimetry, X-ray powder diffractometry and FourierTransform Infra-Red analysis. The results of the solidstate study demonstrated that the freeze-drying methodyields a system with a high degree of amorphisationand yields an inclusion complex.The dissolution profile of the pesticide was affectedby the physico-chemical properties of each solidsystem, the freeze-dried form dissolving more rapidly. However, the physical association of-cyclodextrin and carbaryl enhanced the aqueoussolubility of the insecticide as well. 相似文献
12.
Ostacolo L Russo P De Rosa G La Rotonda MI Maglio G Nese G Spagnuolo G Rengo S Oliva A Quaglia F 《Macromolecular bioscience》2008,8(7):682-689
The production of PEEA microspheres with potential as carriers for protein oral delivery is described. PEEAs with different hydrophilicity were synthesized and characterized. Experiments showed that an increase in copolymer hydrophilicity gave particles less prone to cell interaction. BSA release profiles from PEEA microspheres demonstrated that an increase in polymer hydrophilicity was useful in limiting protein burst and modulating drug delivery rate by increasing PEEA degradability. These results show that fine-tuning of the hydrophilic/hydrophobic properties of PCL is essential for the formulation protein-loaded microspheres with specific properties. 相似文献
13.
Tufano C Peters GW van Puyvelde P Meijer HE 《Journal of colloid and interface science》2008,328(1):48-57
The influence of molecular weight asymmetry across an interface on the transient behavior of the interfacial tension is investigated for two different polymer combinations, polybutadiene (PBD)/polydimethylsiloxane (PDMS) and polybutene (PB)/PDMS. This choice ensures a minor diffuse interface using the first combination and a very diffuse interface in the latter case. Measurements of the interfacial tension as a function of time are carried out using a pendent/sessile drop apparatus at different temperatures ranging from 0 degrees C to 80 degrees C. Variations in the transient interfacial tension are attributed to diffusion of the lower molecular weight components from one phase into the other and the most pronounced changes are measured for the most diffusive systems (low molecular weight and high polydispersity) when diffusion goes from the drop into the matrix. By reversing the phases, only minor changes in the transient interfacial tension are measured. This is due to a fast saturation of the drop-phase since the drop volume is much smaller than that of the continuous phase. In all cases investigated, after a sufficient time a steady value of the interfacial tension is reached. In order to estimate the characteristic diffusion times of the migrating species, a discrete solution of the diffusion equation and a kinetic model from literature are applied. Results obtained are in line with the experimental observations. The importance of a changing interfacial tension on morphology development is studied on dilute (1%) blends, using two in situ techniques: small angle light scattering (SALS) and optical microscopy (OM). The SALS patterns yield the time evolution of the drop size, which is subsequently compared with the morphology following from OM. Depending on the diffusivity of the system, the morphology development is dominated by either diffusion or coalescence. Existing sharp-interface drainage models indeed do not apply for the diffuse blends and an improved quantitative estimation of the value of the critical film thickness is needed. 相似文献
14.
Anna De Masi Immacolata Merola Errico Presutti Yvon Vignaud 《Journal of statistical physics》2009,134(2):243-306
This is the second of two papers on a continuum version of the Potts model, where particles are points in ℝ
d
, d≥2, with a spin which may take S≥3 possible values. Particles with different spins repel each other via a Kac pair potential of range γ
−1, γ>0. In this paper we prove phase transition, namely we prove that if the scaling parameter of the Kac potential is suitably
small, given any temperature there is a value of the chemical potential such that at the given temperature and chemical potential
there exist S+1 mutually distinct DLR measures. 相似文献
15.
Valentina Lo Giudice Immacolata Faraone Maria Roberta Bruno Maria Ponticelli Fabiana Labanca Donatella Bisaccia Carmine Massarelli Luigi Milella Luigi Todaro 《Molecules (Basel, Switzerland)》2021,26(16)
The need to produce an ever-increasing quantity of material products and food resulting from the planet globalization process has contributed to the spread of modern agriculture based on a linear production resulting in the generation of tons of waste. This huge amount of waste is generally accumulated in landfills, causing different environmental problems. Hence, researchers moved on to study the processes used to recover agro-industrial by-products within a circular and sustainable bio-economy concept. A systematic quest on Scopus and PubMed databases was performed to identify the data available to date on recycling agro-industrial by-products of Olea europaea L. This systematic review summarizes the knowledge regarding the use of olive trees by-products for producing animal feed, biocomposites, bioethanol, cellulose pulp, activated carbon, and as a fuel source for energy production. Furthermore, the data regarding the potential biological activity of extracts from olive roots, wood, bark, and pruning were analyzed. Olive trees by-products are, indeed, rich in molecules with antioxidant, antimicrobial, cardioprotective, and anticancer activity, representing a promising candidate for treat several human diseases. 相似文献
16.
Immacolata Anacarso Carla Sabia Simona de Niederhäusern Ramona Iseppi Carla Condò Moreno Bondi 《Natural product research》2019,33(4):606-611
Several species of the genus Acanthamoeba cause human diseases. Treatment of infections involves various problems, emphasising the need to develop alternative antiprotozoal agents. We studied the anti-amoebic activity of Essential Oils (EOs), derived from rosemary (Rosmarinus officinalis L.) and cloves (Syzygium aromaticum L. Merr. & Perry), against Acanthamoeba polyphaga strain. The amoebicidal activity of cloves and rosemary EOs was preliminary demonstrated by the morphology change (modifications in the cell shape, the presence of precipitates in the cytoplasm, autophagic vesicles, membrane blends) of the treated trophozoites. The cell-counts, carried out after staining trophozoites with a Trypan blue solution, revealed that both EOs were active in a dose-dependent manner and in relation to the exposure time. This activity was evident after few hours, with encouraging results obtained in particular with cloves EO, able to act at the lower concentrations and after 1 h, probably for its high eugenol content (65.30%). 相似文献
17.
Immacolata Sigillo Francesco Greco Giuseppe Marrucci 《Liquid crystals》1998,24(3):419-425
The core structure of a disclination line of strength 1 in uniaxial nematics is determined by using a space-dependent mean-field approach somehow based on the rod-like molecular model. It is shown that, due to distortion, biaxiality arises at all points of the defect core, except at the centre line where symmetry dictates uniaxiality; the orientational distribution of the rod-like molecules is there 'oblate', however. Although, as is well known, the configuration of a 1 defect is stable only under limiting conditions (as compared with either escaping in the axial direction or splitting into two 1/2 lines), the simple example developed here is indicative of a method which can readily be extended to more realistic, if mathematically more complex, situations such as 1/2 lines, layers close to solid boundaries, etc. 相似文献
18.
Dr. Immacolata Speciale Dr. Flaviana Di Lorenzo Dr. Valentina Gargiulo Dr. Gitte Erbs Prof. Mari-Anne Newman Prof. Antonio Molinaro Prof. Cristina De Castro 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(16):6430-6436
The lipopolysaccharide (LPS) O-antigen structure of the plant pathogen Rhizobium radiobacter strain TT9 and its possible role in a plant-microbe interaction was investigated. The analyses disclosed the presence of two O-antigens, named Poly1 and Poly2. The repetitive unit of Poly2 constitutes a 4-α-l -rhamnose linked to a 3-α-d -fucose residue. Surprisingly, Poly1 turned out to be a novel type of biopolymer in which the repeating unit is formed by a monosaccharide and an amino-acid derivative, so that the polymer has alternating glycosidic and amidic bonds joining the two units: 4-amino-4-deoxy-3-O-methyl-d -fucose and (2′R,3′R,4′S)-N-methyl-3′,4′-dihydroxy-3′-methyl-5′-oxoproline). Differently from the O-antigens of LPSs from other pathogenic Gram-negative bacteria, these two O-antigens do not activate the oxidative burst, an early innate immune response in the model plant Arabidopsis thaliana, explaining at least in part the ability of this R. radiobacter strain to avoid host defenses during a plant infection process. 相似文献
19.
Annalisa Vilasi Immacolata Fiume Paolo Pace Mosè Rossi Gabriella Pocsfalvi 《Journal of mass spectrometry : JMS》2013,48(11):1188-1198
Owning to their anion‐exchange properties, titanium and zirconium dioxides are widely used in phosphopeptide enrichment and purification protocols. The physical and chemical characteristics of the particles can significantly influence the loading capacity, the capture efficiency and phosphopeptide specificity and thus the outcome of the analyses. Although there are a number of protocols and commercial kits available for phosphopeptide purification, little data are found in the literature on the choice of the enrichment media. Here, we studied the influence of particle size on the affinity capture of phosphopeptides by TiO2 and ZrO2. Bovine milk casein derived phosphopeptides were enriched by micro and nanoparticles using a single‐tube in‐solution protocol at different peptide‐to‐beads ratio ranging from 1 : 1 to 1 : 200. Unsupervised hierarchical cluster analysis based on the whole set of Matrix Assisted Laser Desorption/Ionization time‐of‐flight mass spectra of the phosphopeptide enriched samples revealed 62 clustered peptide peaks and shows that nanoparticles have considerably higher enrichment capacity than bulk microparticles. Moreover, ZrO2 particles have higher enrichment capacity than TiO2. The selectivity and specificity of the enrichment was studied by monitoring the ion abundances of monophosphorylated, multiphosphorylated and non‐phosphorylated casein‐derived peptide peaks at different peptide‐to‐beads ratios. Comparison of the resulting plots enabled the determination of the optimal peptide‐to‐beads ratios for the different beads studied and showed that nano‐TiO2 have higher selectivity for phosphopeptides than nano‐ZrO2 particles. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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