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Zappaterra F, Renzi M, Piccardo M, Spennato M, Asaro F, Di Serio M, Vitiello R, Turco R, Todea A, Gardossi L. Understanding Marine Biodegradation of Bio-Based Oligoesters and Plasticizers. Polymers (Basel) 2023; 15:polym15061536. [PMID: 36987316 PMCID: PMC10054732 DOI: 10.3390/polym15061536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/08/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
The study reports the enzymatic synthesis of bio-based oligoesters and chemo-enzymatic processes for obtaining epoxidized bioplasticizers and biolubricants starting from cardoon seed oil. All of the molecules had MW below 1000 g mol-1 and were analyzed in terms of marine biodegradation. The data shed light on the effects of the chemical structure, chemical bond lability, thermal behavior, and water solubility on biodegradation. Moreover, the analysis of the biodegradation of the building blocks that constituted the different bio-based products allowed us to distinguish between different chemical and physicochemical factors. These hints are of major importance for the rational eco-design of new benign bio-based products. Overall, the high lability of ester bonds was confirmed, along with the negligible effect of the presence of epoxy rings on triglyceride structures. The biodegradation data clearly indicated that the monomers/building blocks undergo a much slower process of abiotic or biotic transformations, potentially leading to accumulation. Therefore, the simple analysis of the erosion, hydrolysis, or visual/chemical disappearance of the chemical products or plastic is not sufficient, but ecotoxicity studies on the effects of such small molecules are of major importance. The use of natural feedstocks, such as vegetable seed oils and their derivatives, allows the minimization of these risks, because microorganisms have evolved enzymes and metabolic pathways for processing such natural molecules.
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Affiliation(s)
- Federico Zappaterra
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Monia Renzi
- Department of Life Sciences, University of Trieste, Via L. Girgieri 10, 34127 Trieste, Italy
| | - Manuela Piccardo
- Department of Life Sciences, University of Trieste, Via L. Girgieri 10, 34127 Trieste, Italy
| | - Mariachiara Spennato
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Martino Di Serio
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, 80126 Napoli, Italy
| | - Rosa Vitiello
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, 80126 Napoli, Italy
| | - Rosa Turco
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, 80126 Napoli, Italy
- Institute for Polymers, Composites and Biomaterials, National Council of Research, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | - Anamaria Todea
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Lucia Gardossi
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
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2
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Danielli C, van Langen L, Boes D, Asaro F, Anselmi S, Provenza F, Renzi M, Gardossi L. 2,5-Furandicarboxaldehyde as a bio-based crosslinking agent replacing glutaraldehyde for covalent enzyme immobilization. RSC Adv 2022; 12:35676-35684. [PMID: 36545099 PMCID: PMC9748790 DOI: 10.1039/d2ra07153c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022] Open
Abstract
In the quest for a bio-based and safer substitute for glutaraldehyde, we have investigated 2,5 diformylfuran (DFF) as bifunctional crosslinking agent for the covalent immobilization of glucoamylase on amino-functionalized methacrylic resins. Immobilization experiments and systematic comparison with glutaraldehyde at four different concentrations for the activation step showed that DFF leads to comparable enzymatic activities at all tested concentrations. Continuous flow experiment confirms a similar long term stability of the immobilized formulations obtained with the two crosslinkers. The NMR study of DFF in aqueous solution evidenced a much simpler behaviour as compared to glutaraldehyde, since no enolic forms can form and only a mono-hydrated form was observed. Unlike in the case of glutaraldehyde, DFF reacts covalently with the primary amino groups via imine bond formation only. Nevertheless, the stability of the covalent immobilization was confirmed also at acidic pH (4.5), most probably because of the higher stability of the imine bonds formed with the aromatic aldehydes. In terms of toxicity DFF has the advantage of being poorly soluble in water and, more importantly, poorly volatile as compared to glutaraldehyde, which displays severe respiratory toxicity. We have performed preliminary ecotoxicity assays using Aliivibrio fischeri, a marine bacterium, evidencing comparable behaviour (below the toxicity threshold) for both dialdehydes at the tested concentrations.
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Affiliation(s)
- Chiara Danielli
- Department of Chemical and Pharmaceutical Sciences, University of TriesteVia L. Giorgieri 134127 TriesteItaly,ViaZym B.V.Molengraaffsingel 102629 JDDelftThe Netherlands
| | | | - Deborah Boes
- ViaZym B.V.Molengraaffsingel 102629 JDDelftThe Netherlands,Department of Biotechnology, Delft University of TechnologyVan der Maasweg 9NL-2629 HZ DelftThe Netherlands
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of TriesteVia L. Giorgieri 134127 TriesteItaly
| | - Serena Anselmi
- Bioscience Research CenterVia Aurelia Vecchia, 32, 58015 OrbetelloGRItaly
| | - Francesca Provenza
- Bioscience Research CenterVia Aurelia Vecchia, 32, 58015 OrbetelloGRItaly,Department of Life Science (DSV), University of TriesteVia L. Giorgieri 1034127 TriesteItaly
| | - Monia Renzi
- Department of Life Science (DSV), University of TriesteVia L. Giorgieri 1034127 TriesteItaly
| | - Lucia Gardossi
- Department of Chemical and Pharmaceutical Sciences, University of TriesteVia L. Giorgieri 134127 TriesteItaly
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Spennato M, Roggero OM, Varriale S, Asaro F, Cortesi A, Kašpar J, Tongiorgi E, Pezzella C, Gardossi L. Neuroprotective Properties of Cardoon Leaves Extracts against Neurodevelopmental Deficits in an In Vitro Model of Rett Syndrome Depend on the Extraction Method and Harvest Time. Molecules 2022; 27:molecules27248772. [PMID: 36557905 PMCID: PMC9783035 DOI: 10.3390/molecules27248772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022]
Abstract
This study investigates the bioactive properties of different extracts of cardoon leaves in rescuing neuronal development arrest in an in vitro model of Rett syndrome (RTT). Samples were obtained from plants harvested at different maturity stages and extracted with two different methodologies, namely Naviglio® and supercritical carbon dioxide (scCO2). While scCO2 extracts more hydrophobic fractions, the Naviglio® method extracts phenolic compounds and less hydrophobic components. Only the scCO2 cardoon leaves extract obtained from plants harvested in spring induced a significant rescue of neuronal atrophy in RTT neurons, while the scCO2 extract from the autumn harvest stimulated dendrite outgrowth in Wild-Type (WT) neurons. The scCO2 extracts were the richest in squalene, 3ß-taraxerol and lupeol, with concentrations in autumn harvest doubling those in spring harvest. The Naviglio® extract was rich in cynaropicrin and exerted a toxic effect at 20 µM on both WT and RTT neurons. When cynaropicrin, squalene, lupeol and 3ß-taraxerol were tested individually, no positive effect was observed, whereas a significant neurotoxicity of cynaropicrin and lupeol was evident. In conclusion, cardoon leaves extracts with high content of hydrophobic bioactive molecules and low cynaropicrin and lupeol concentrations have pharmacological potential to stimulate neuronal development in RTT and WT neurons in vitro.
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Affiliation(s)
- Mariachiara Spennato
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Ottavia Maria Roggero
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 5, 34127 Trieste, Italy
| | - Simona Varriale
- Department of Chemical Sciences, University Federico II of Naples, Via Cinthia, 4, 80126 Napoli, Italy
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Angelo Cortesi
- Department of Engineering and Architecture, University of Trieste, Via Alfonso Valerio 6/A, 34127 Trieste, Italy
| | - Jan Kašpar
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Enrico Tongiorgi
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 5, 34127 Trieste, Italy
| | - Cinzia Pezzella
- Department of Chemical Sciences, University Federico II of Naples, Via Cinthia, 4, 80126 Napoli, Italy
| | - Lucia Gardossi
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
- Correspondence:
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Todea A, Fortuna S, Ebert C, Asaro F, Tomada S, Cespugli M, Hollan F, Gardossi L. Rational Guidelines for the Two-Step Scalability of Enzymatic Polycondensation: Experimental and Computational Optimization of the Enzymatic Synthesis of Poly(glycerolazelate). ChemSusChem 2022; 15:e202102657. [PMID: 35199480 PMCID: PMC9320960 DOI: 10.1002/cssc.202102657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/11/2022] [Indexed: 06/14/2023]
Abstract
The lipase-catalyzed polycondensation of azelaic acid and glycerol is investigated according to a Design-of-Experiment approach that helps to elucidate the effect of experimental variables on monomer conversion, Mn and regioselectivity of acylation of glycerol. Chemometric analysis shows that after 24 h the reaction proceeds regardless of the presence of the enzyme. Accordingly, the biocatalyst was removed after a first step of synthesis and the chain elongation continued at 80 °C. That allowed the removal of the biocatalyst and the preservation of its activity: pre-requites for efficient applicability at industrial scale. The experimental study, combined with docking-based computational analysis, provides rational guidelines for the optimization of the regioselective acylation of glycerol. The process is scaled up to 73.5 g of monomer. The novelty of the present study is the rigorous control of the reaction conditions and of the integrity of the immobilized biocatalyst, which serve to avoiding any interference of free enzyme or fines released in the reaction mixture. The quantitative analysis of the effect of experimental conditions and the overcoming of some major technical bottlenecks for the scalability of enzymatic polycondensation opens new scenarios for industrial exploitation.
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Affiliation(s)
- Anamaria Todea
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
| | - Sara Fortuna
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
- Current address: CONCEPT Lab, Istituto Italiano di Tecnologia (IIT)I-16152GenovaItaly
| | - Cynthia Ebert
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
| | - Stefano Tomada
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
| | - Marco Cespugli
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
| | - Fabio Hollan
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
| | - Lucia Gardossi
- Department of Chemical and Pharmaceutical SciencesInstitution University of TriesteAddress 1 Via L. Giorgieri 134127TriesteItaly
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5
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Todea A, Deganutti C, Spennato M, Asaro F, Zingone G, Milizia T, Gardossi L. Azelaic Acid: A Bio-Based Building Block for Biodegradable Polymers. Polymers (Basel) 2021; 13:4091. [PMID: 34883592 PMCID: PMC8659112 DOI: 10.3390/polym13234091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/05/2021] [Accepted: 11/19/2021] [Indexed: 11/17/2022] Open
Abstract
Azelaic acid is a dicarboxylic acid containing nine C atoms, industrially obtained from oleic acid. Besides its important properties and pharmacological applications, as an individual compound, azelaic acid has proved to be a valuable bio-based monomer for the synthesis of biodegradable and sustainable polymers, plasticizers and lubricants. This review discusses the studies and the state of the art in the field of the production of azelaic acid from oleic acid, the chemical and enzymatic synthesis of bio-based oligo and polyester and their properties, including biodegradability and biocompostability.
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Affiliation(s)
- Anamaria Todea
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy; (A.T.); (C.D.); (M.S.); (F.A.); (G.Z.)
| | - Caterina Deganutti
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy; (A.T.); (C.D.); (M.S.); (F.A.); (G.Z.)
| | - Mariachiara Spennato
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy; (A.T.); (C.D.); (M.S.); (F.A.); (G.Z.)
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy; (A.T.); (C.D.); (M.S.); (F.A.); (G.Z.)
| | - Guglielmo Zingone
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy; (A.T.); (C.D.); (M.S.); (F.A.); (G.Z.)
| | | | - Lucia Gardossi
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy; (A.T.); (C.D.); (M.S.); (F.A.); (G.Z.)
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Asaro F, Boga C, Zorzi RD, Geremia S, Gigli L, Nitti P, Semeraro S. ( R)-10-Hydroxystearic Acid: Crystals vs. Organogel. Int J Mol Sci 2020; 21:ijms21218124. [PMID: 33143206 PMCID: PMC7662707 DOI: 10.3390/ijms21218124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 12/03/2022] Open
Abstract
The chiral (R)-10-hydroxystearic acid ((R)-10-HSA) is a positional homologue of both (R)-12-HSA and (R)-9-HSA with the OH group in an intermediate position. While (R)-12-HSA is one of the best-known low-molecular-weight organogelators, (R)-9-HSA is not, but it forms crystals in several solvents. With the aim to gain information on the structural role of hydrogen-bonding interactions of the carbinol OH groups, we investigated the behavior of (R)-10-HSA in various solvents. This isomer displays an intermediate behavior between (R)-9 and (R)-12-HSA, producing a stable gel exclusively in paraffin oil, while it crystallizes in other organic solvents. Here, we report the X-ray structure of a single crystal of (R)-10-HSA as well as some structural information on its polymorphism, obtained through X-ray Powder Diffraction (XRPD) and Infrared Spectroscopy (IR). This case study provides new elements to elucidate the structural determinants of the microscopic architectures that lead to the formation of organogels of stearic acid derivatives.
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Affiliation(s)
- Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy; (S.G.); (P.N.); (S.S.)
- Correspondence: (F.A.); (R.D.Z.); Tel.: +39-040-5583951 (F.A.)
| | - Carla Boga
- Department of Industrial Chemistry “Toso Montanari”, University of Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy;
| | - Rita De Zorzi
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy; (S.G.); (P.N.); (S.S.)
- Correspondence: (F.A.); (R.D.Z.); Tel.: +39-040-5583951 (F.A.)
| | - Silvano Geremia
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy; (S.G.); (P.N.); (S.S.)
| | - Lara Gigli
- Elettra–Sincrotrone Trieste, S.S. 14 Km 163.5 in Area Science Park, Basovizza, 34149 Trieste, Italy;
| | - Patrizia Nitti
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy; (S.G.); (P.N.); (S.S.)
| | - Sabrina Semeraro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy; (S.G.); (P.N.); (S.S.)
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Pizzolitto C, Cok M, Asaro F, Scognamiglio F, Marsich E, Lopez F, Donati I, Sacco P. On the Mechanism of Genipin Binding to Primary Amines in Lactose-Modified Chitosan at Neutral pH. Int J Mol Sci 2020; 21:E6831. [PMID: 32957651 PMCID: PMC7554727 DOI: 10.3390/ijms21186831] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 01/22/2023] Open
Abstract
The present manuscript deals with the elucidation of the mechanism of genipin binding by primary amines at neutral pH. UV-VIS and CD measurements both in the presence of oxygen and in oxygen-depleted conditions, combined with computational analyses, led to propose a novel mechanism for the formation of genipin derivatives. The indications collected with chiral and achiral primary amines allowed interpreting the genipin binding to a lactose-modified chitosan (CTL or Chitlac), which is soluble at all pH values. Two types of reaction and their kinetics were found in the presence of oxygen: (i) an interchain reticulation, which involves two genipin molecules and two polysaccharide chains, and (ii) a binding of one genipin molecule to the polymer chain without chain-chain reticulation. The latter evolves in additional interchain cross-links, leading to the formation of the well-known blue iridoid-derivatives.
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Affiliation(s)
- Chiara Pizzolitto
- Department of Medical, Surgical, and Health Sciences, University of Trieste, piazza dell’Ospitale 1, 34127 Trieste, Italy; (C.P.); (F.S.); (E.M.)
| | - Michela Cok
- Department of Life Sciences, University of Trieste, via Licio Giorgieri 5, 34127 Trieste, Italy; (M.C.); (I.D.)
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy;
| | - Francesca Scognamiglio
- Department of Medical, Surgical, and Health Sciences, University of Trieste, piazza dell’Ospitale 1, 34127 Trieste, Italy; (C.P.); (F.S.); (E.M.)
| | - Eleonora Marsich
- Department of Medical, Surgical, and Health Sciences, University of Trieste, piazza dell’Ospitale 1, 34127 Trieste, Italy; (C.P.); (F.S.); (E.M.)
| | - Francesco Lopez
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise, Via De Sanctis, I-86100 Campobasso, Italy;
| | - Ivan Donati
- Department of Life Sciences, University of Trieste, via Licio Giorgieri 5, 34127 Trieste, Italy; (M.C.); (I.D.)
| | - Pasquale Sacco
- Department of Life Sciences, University of Trieste, via Licio Giorgieri 5, 34127 Trieste, Italy; (M.C.); (I.D.)
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Scarabel L, Garziera M, Fortuna S, Asaro F, Toffoli G, Geremia S. Soluble HLA-G expression levels and HLA-G/irinotecan association in metastatic colorectal cancer treated with irinotecan-based strategy. Sci Rep 2020; 10:8773. [PMID: 32471996 PMCID: PMC7260212 DOI: 10.1038/s41598-020-65424-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 04/27/2020] [Indexed: 02/07/2023] Open
Abstract
We here explore the soluble Human Leukocyte Antigen-G (sHLA-G) expression level as clinical biomarker in metastatic colorectal cancer (mCRC). To this aim the sHLA-G protein was measured in plasma samples of 40 patients with mCRC treated with the FOLFIRI (irinotecan (CPT-11) plus 5-fluorouracil (5-FU) and leucovorin (LV)) regimen. The results suggest a link between HLA-G levels and irinotecan (CPT-11) pharmacokinetic, leading to hypothesize a molecular interaction between sHLA-G and CPT-11. This interaction was confirmed experimentally by fluorescence spectroscopy. HLA-G is known to exist in a number of polymorphs that affect both the protein expression levels and its peptide-binding cleft. The interaction between HLA-G polymorphs and CPT-11 was explored by means of computational modelling, confirming the hypothesis that CPT-11 could actually target the peptide binding cleft of the most common HLA-G polymorphs.
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Affiliation(s)
- Lucia Scarabel
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico (CRO), IRCCS, 33081, Aviano, Italy
| | - Marica Garziera
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico (CRO), IRCCS, 33081, Aviano, Italy
| | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127, Trieste, Italy.
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127, Trieste, Italy
| | - Giuseppe Toffoli
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico (CRO), IRCCS, 33081, Aviano, Italy
| | - Silvano Geremia
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127, Trieste, Italy
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Bahojb Noruzi E, Kheirkhahi M, Shaabani B, Geremia S, Hickey N, Asaro F, Nitti P, Kafil HS. Design of a Thiosemicarbazide-Functionalized Calix[4]arene Ligand and Related Transition Metal Complexes: Synthesis, Characterization, and Biological Studies. Front Chem 2019; 7:663. [PMID: 31649917 PMCID: PMC6794423 DOI: 10.3389/fchem.2019.00663] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 09/17/2019] [Indexed: 12/11/2022] Open
Abstract
In this study, we synthesized a new thiosemicarbazide-functionalized calix[4]arene L and its Co2+, Ni2+, Cu2+, and Zn2+ transition metal complexes. For characterization several techniques were employed: Fourier-transform infrared (FT-IR), 1H nuclear magnetic resonance (NMR), 13C-NMR, 15N-NMR, correlation spectroscopy (COZY), nuclear Overhauser enhancement spectroscopy (NOESY), electrospray ionization (ESI)-mass spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and elemental analysis. To explore the capability of the thiosemicarbazide function hosted on a calix[4]arene scaffold for growth inhibition of bacteria, fungi, and cancerous tumor cells, a series of biological evaluations were performed. For L, the antimicrobial tests revealed a higher antibacterial activity against gram-positive Bacillus subtilis and a lower activity against gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), whereas the gram-positive Staphylococcus aureus shows resistance. All examined metal derivatives show an enhancement of the antibacterial activity against gram-negative E. coli bacteria, with a more significant improvement for the Ni2+ and Zn2+ complexes. MTT assays showed a considerable in vitro anticancer activity of Co2+, Ni2+, and Cu2+ complexes against Saos-2 bone cancer cell lines. The activity is ascribable to the inorganic ions rather than calixarene ligand. Hemolysis assay results demonstrated that all compounds have high blood compatibility.
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Affiliation(s)
- Ehsan Bahojb Noruzi
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
| | - Mahsa Kheirkhahi
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
| | - Behrouz Shaabani
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
| | - Silvano Geremia
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Neal Hickey
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Patrizia Nitti
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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10
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Asaro F, Boga C, Demitri N, De Zorzi R, Drioli S, Gigli L, Micheletti G, Nitti P, Zangrando E. X-Ray Crystal Structures and Organogelator Properties of (R)-9-Hydroxystearic Acid. Molecules 2019; 24:molecules24152854. [PMID: 31390777 PMCID: PMC6695734 DOI: 10.3390/molecules24152854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/02/2019] [Accepted: 08/03/2019] [Indexed: 11/22/2022]
Abstract
(R)-9-hydroxystearic acid, (R)-9-HSA, is a chiral nonracemic hydroxyacid of natural origin possessing interesting properties as an antiproliferative agent against different cancer types. Considering its potential application for medical and pharmaceutical purposes, the structures and rheological properties of (R)-9-HSA were investigated. Oscillatory rheology measurements reveal that (R)-9-HSA gels only paraffin oil, with less efficiency and thermal stability than its positional isomer (R)-12-HSA. Conversely, (R)-9-HSA affords crystals from methanol, acetonitrile, and carbon tetrachloride. The single crystal structures obtained both at 293 K and 100 K show non-centrosymmetric twisted carboxylic acid dimers linked at the midchain OHs into long, unidirectional chains of hydrogen bonds, owing to head-tail ordering of the molecules. Synchrotron X-ray powder diffraction experiments, performed on the solids obtained from different solvents, show the occurrence of polymorphism in paraffin oil and through thermal treatment of the solid from methanol.
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Affiliation(s)
- Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy.
| | - Carla Boga
- Department of Industrial Chemistry "Toso Montanari", University of Bologna, viale del Risorgimento 4, 40136 Bologna, Italy
| | - Nicola Demitri
- Elettra-Sincrotrone Trieste, S.S. 14 Km 163.5 in Area Science Park, Basovizza, 34149 Trieste, Italy
| | - Rita De Zorzi
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy
| | - Sara Drioli
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy
| | - Lara Gigli
- Elettra-Sincrotrone Trieste, S.S. 14 Km 163.5 in Area Science Park, Basovizza, 34149 Trieste, Italy
| | - Gabriele Micheletti
- Department of Industrial Chemistry "Toso Montanari", University of Bologna, viale del Risorgimento 4, 40136 Bologna, Italy
| | - Patrizia Nitti
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy.
| | - Ennio Zangrando
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy
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Guarneri A, Cutifani V, Cespugli M, Pellis A, Vassallo R, Asaro F, Ebert C, Gardossi L. Functionalization of Enzymatically Synthesized Rigid Poly(itaconate)sviaPost‐Polymerization Aza‐Michael Addition of Primary Amines. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201900055] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Alice Guarneri
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
- Laboratory of Organic ChemistryWageningen University & Research Stippeneng 4 6708 WE Wageningen The Netherlands
| | - Viola Cutifani
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
| | - Marco Cespugli
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
| | - Alessandro Pellis
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
- University of YorkDepartment of Chemistry, Green Chemistry Centre of Excellence YO10 5DD York UK
| | - Roberta Vassallo
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
| | - Fioretta Asaro
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
| | - Cynthia Ebert
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
| | - Lucia Gardossi
- Laboratory of Applied and Computational Biocatalysis, Dipartimento di Scienze Chimiche e FarmaceuticheUniversità degli Studi di Trieste Via Licio Giorgieri 1 34127 Trieste Italy
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Furlani F, Sacco P, Scognamiglio F, Asaro F, Travan A, Borgogna M, Marsich E, Cok M, Paoletti S, Donati I. Nucleation, reorganization and disassembly of an active network from lactose-modified chitosan mimicking biological matrices. Carbohydr Polym 2019; 208:451-456. [DOI: 10.1016/j.carbpol.2018.12.096] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 12/20/2018] [Accepted: 12/30/2018] [Indexed: 01/07/2023]
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Asaro F, Drioli S, Forzato C, Nitti P. An Efficient Synthesis of Chiral Non‐Racemic Hydroxyalkanoic Acids by Olefin Cross‐Metathesis Reactions. ChemistrySelect 2018. [DOI: 10.1002/slct.201802989] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Fioretta Asaro
- Dipartimento di Scienze Chimiche e FarmaceuticheUniversità di Trieste via Licio Giorgieri 1 34127 Trieste Italy
| | - Sara Drioli
- Dipartimento di Scienze Chimiche e FarmaceuticheUniversità di Trieste via Licio Giorgieri 1 34127 Trieste Italy
| | - Cristina Forzato
- Dipartimento di Scienze Chimiche e FarmaceuticheUniversità di Trieste via Licio Giorgieri 1 34127 Trieste Italy
| | - Patrizia Nitti
- Dipartimento di Scienze Chimiche e FarmaceuticheUniversità di Trieste via Licio Giorgieri 1 34127 Trieste Italy
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Milcovich G, Antunes FE, Grassi M, Asaro F. Stabilization of unilamellar catanionic vesicles induced by β-cyclodextrins: A strategy for a tunable drug delivery depot. Int J Pharm 2018; 548:474-479. [DOI: 10.1016/j.ijpharm.2018.07.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 07/05/2018] [Accepted: 07/06/2018] [Indexed: 12/01/2022]
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Sacco P, Cok M, Asaro F, Paoletti S, Donati I. The role played by the molecular weight and acetylation degree in modulating the stiffness and elasticity of chitosan gels. Carbohydr Polym 2018; 196:405-413. [DOI: 10.1016/j.carbpol.2018.05.060] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 01/28/2023]
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Milcovich G, Antunes FE, Farra R, Grassi G, Grassi M, Asaro F. Modulating carbohydrate-based hydrogels as viscoelastic lubricant substitute for articular cartilages. Int J Biol Macromol 2017; 102:796-804. [DOI: 10.1016/j.ijbiomac.2017.04.079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Revised: 04/20/2017] [Accepted: 04/22/2017] [Indexed: 10/19/2022]
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Sacco P, Paoletti S, Cok M, Asaro F, Abrami M, Grassi M, Donati I. Insight into the ionotropic gelation of chitosan using tripolyphosphate and pyrophosphate as cross-linkers. Int J Biol Macromol 2016; 92:476-483. [DOI: 10.1016/j.ijbiomac.2016.07.056] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 07/14/2016] [Indexed: 10/21/2022]
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Milcovich G, Antunes F, Golob S, Farra R, Grassi M, Voinovich D, Grassi G, Asaro F. Thermo-responsive hydrogels from cellulose-based polyelectrolytes and catanionic vesicles for biomedical application. J Biomed Mater Res A 2016; 104:1668-79. [DOI: 10.1002/jbm.a.35698] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 02/23/2016] [Accepted: 02/25/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Gesmi Milcovich
- Department of Chemical and Pharmaceutical Sciences; University of Trieste; via L. Giorgieri 1 Trieste I-34127 Italy
| | - Filipe Antunes
- Chemistry Department; University of Coimbra; Coimbra 3004-535 Portugal
| | - Samuel Golob
- Department of Chemical and Pharmaceutical Sciences; University of Trieste; P.le Europa, 1 Trieste I-34127 Italy
| | - Rossella Farra
- Department of Engineering and Architecture; University of Trieste; Trieste I-34127 Italy
| | - Mario Grassi
- Department of Engineering and Architecture; University of Trieste; Trieste I-34127 Italy
| | - Dario Voinovich
- Department of Chemical and Pharmaceutical Sciences; University of Trieste; P.le Europa, 1 Trieste I-34127 Italy
| | - Gabriele Grassi
- Department of Life Sciences; University Hospital of Cattinara; Trieste 34100 Italy
| | - Fioretta Asaro
- Department of Chemical and Pharmaceutical Sciences; University of Trieste; via L. Giorgieri 1 Trieste I-34127 Italy
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Falsone G, Cateni F, Katusian F, Wagner H, Seligmann O, Pellizer G, Asaro F. Constituents of Euphorbiaceae, 10. Comm. / New Cerebrosides from Euphorbia characias L. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-1993-0814] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Four new cerebrosides C-1 – C-4 were isolated from the latex of Euphorbia characias L. On the basis of spectral evidences and chemical reactions they were characterized as (2S, 3S, 4R, 5R, 6Z)-1-O-(β-D-glucopyranosyl)-2N-[(2'R)-2′-hydroxy-(15′Z)-tetracosenoyl]-6(Z)-octadecene-1,3,4,5-tetraol-2-amino (C-1), (2 S, 3 S, 4 R, 5 R, 6 Z)-1-O-(β-D-glucopyranosyl)-2N-[(2′ R)-2′hydroxy-(17′ Z)-hexacosenoyl]-6(Z)-octadecene-1,3,4,5-tetraol- 2-amino (C-2), (2S, 3S, 4R, 5R, 6Z)-1-O-(β-D-glucopyranosyl)-2N-[(2′R)-2′-hydroxy-(19′Z)-octacosenoyl]-6-(Z)-octadecene-1,3,4,5-tetraol-2-amino (C-3) and (2 S, 3 S, 4 R, 5 R, 6 Z)-1-O-(β-D-glucopyranosyl)-2N-[(2′R)-2′-hydroxy-octacosanoyl]-6-(Z)-octadecene-1,3,4,5-tetraol-2-amino (C-4).
Reversed phase column flash chromatography was effective for the isolation of the cerebrosides. FAB-MS spectrometry, 1H NMR, 13C NMR analysis and chemical reactions were useful in providing information for the structure elucidation.
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Affiliation(s)
- G. Falsone
- Department of Pharmaceutical Sciences, University of Trieste, P.zle Europa 1, I-34127 Trieste
| | - F. Cateni
- Department of Pharmaceutical Sciences, University of Trieste, P.zle Europa 1, I-34127 Trieste
| | - F. Katusian
- Department of Pharmaceutical Sciences, University of Trieste, P.zle Europa 1, I-34127 Trieste
| | - H. Wagner
- Institut für Pharmazeutische Biologie der Universität München, Karlstraße 29, D-80333 München
| | - O. Seligmann
- Institut für Pharmazeutische Biologie der Universität München, Karlstraße 29, D-80333 München
| | - G. Pellizer
- Department of Chemical Sciences, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste
| | - F. Asaro
- Department of Chemical Sciences, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste
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Abrami M, D'Agostino I, Milcovich G, Fiorentino S, Farra R, Asaro F, Lapasin R, Grassi G, Grassi M. Physical characterization of alginate-Pluronic F127 gel for endoluminal NABDs delivery. Soft Matter 2014; 10:729-737. [PMID: 24651920 DOI: 10.1039/c3sm51873f] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Here we focus the attention on the physical characteristics of a highly biocompatible hydrogel made up of crosslinked alginate and Pluronic F127 (PF127). This is a composite polymeric blend we propose for artery endoluminal delivery of an emerging class of molecules named nucleic acid based drugs (NABDs). The physical characterization of our composite gel, i.e. mesh size distribution and PF127-alginate mutual organization after crosslinking, can significantly determine the NABDs release kinetics. Thus, to explore these aspects, different technical approaches, i.e. rheology, low/high field NMR and TEM, were used. While rheology provided information at the macroscopic and nano-level, the other three approaches gave details at the nano-level. We observe that Pluronic micelles, organizing in cubic ordered domains, generate, upon alginate crosslinking, the formation of meshes (≈ 150 nm) larger than those occurring in a Pluronic-free alginate network (≈ 25 nm). Nevertheless, smaller alginate meshes are still on and can just host un-structured Pluronic micelles and water. Accordingly, the gel structure is quite inhomogeneous, where big meshes (filled by crystalline Pluronic) co-exist with smaller meshes (hosting water and un-structured PF127 micelles). While big meshes offer a considerable hindering action on a diffusing solute, smaller ones represent a sort of free space where solute diffusion is faster. The presence of big and small meshes indicates that drug release may follow a double kinetics characterized by a fast and slow release. Notably, this behavior is considered appropriate for endoluminal drug release to the arterial wall.
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Affiliation(s)
- Michela Abrami
- Department of Engineering and Architecture, University of Trieste, Via Alfonso Valerio, 6/A, I-34127 Trieste, Italy.
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Asaro F, Feruglio L, Galantini L, Nardelli A. 23 Na and 35/37 Cl as NMR probes of growth and shape of sodium taurodeoxycholate micellar aggregates in the presence of NaCl. J Colloid Interface Sci 2013; 392:281-287. [DOI: 10.1016/j.jcis.2012.09.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 09/18/2012] [Accepted: 09/20/2012] [Indexed: 12/01/2022]
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Coviello T, Matricardi P, Alhaique F, Farra R, Tesei G, Fiorentino S, Asaro F, Milcovich G, Grassi M. Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations. EXPRESS POLYM LETT 2013. [DOI: 10.3144/expresspolymlett.2013.71] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Asaro F, Savko N. Resolution of a nonionic surfactant oligomeric mixture by means of DOSY with inverse micelle assistance. Magn Reson Chem 2011; 49:195-198. [PMID: 21387400 DOI: 10.1002/mrc.2732] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 12/28/2010] [Accepted: 01/10/2011] [Indexed: 05/30/2023]
Abstract
DOSY is a recognized, efficient technique in the analysis of mixtures. It relies on the differences in self-diffusion coefficients, which are determined by the molecular size. Nowadays, efforts are directed towards devising matrices able to interact with the components of the mixture with differential affinity, and therefore capable to interfere with the diffusion processes and to display resolving power towards species of close, or even equal molecular weight, like isomers. Usually, commercial nonionic surfactants are mixtures of oligomeric species, since the head group, which is a short polyoxyehtylene chain, is somewhat polydisperse. The embedment of Igepal CA-520, 5 polyoxyethylene iso-octylphenyl ether, in an inverse microemulsion led to the separation of (1)H signals of the various oligomeric components. This ensued from the differential partitioning between the oil and the surface of the inverse micelles, which depends on the ethyleneoxide number (EON) of the head groups. Thus, it was possible to ascertain that the length distribution of the polyethyleneoxide chains is ingood agreement with the Poisson distribution theoretically predicted for the polymerization of ethylene oxide. The DOSY spectrum contributed to the assignment of the signals and afforded the partition degree, between the two environments, for each individual oligomeric species, providing further insight into nonionic inverse microemulsions, at present widely employed reaction media in the nanotechnological syntheses.
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Affiliation(s)
- Fioretta Asaro
- Department of Chemical Sciences, University of Trieste, Trieste, Italy.
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Asaro F, Benedetti A, Freris I, Riello P, Savko N. Evolution of the nonionic inverse microemulsion-acid-TEOS system during the synthesis of nanosized silica via the sol-gel process. Langmuir 2010; 26:12917-12925. [PMID: 20604556 DOI: 10.1021/la101737x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The cyclohexane-igepal inverse microemulsion, comprehensively established for the synthesis of silica nanoparticles in an ammonia-catalyzed sol-gel process, was alternatively studied with an acid-catalyzed sol-gel process. Tetraethyl orthosilicate (TEOS) was used as the silica precursor, while two different aqueous phases containing either HNO(3) or HCl at two different concentrations, 0.1 and 0.05 M, were examined in the presence and in the absence of NaF, a catalyst of the condensation step. The evolution of the overall reacting system, specifically hydrolysis and polycondensation of reaction intermediates, was monitored in situ by time-resolved small-angle X-ray scattering. No size variation of the inverse micelles was detected throughout the sol-gel process. Conversely, the density of the micellar core increased after a certain time interval, indicating the presence of the polycondensation product. The IR spectra of the reacting mixture were in agreement with such a hypothesis. (1)H and (13)C NMR measurements provided information on the soluble species, the surfactant, and TEOS. The TEOS consumption was well fitted by means of an exponential decay, suggesting that a first-order kinetics for TEOS transpires in the various systems examined, with rate constants dependent not only on the acid concentration but also on its nature (anion specific effect), on the presence of NaF, and on the amount of water in the core of the inverse micelle. The self-diffusion coefficients, determined by means of PGSTE NMR, proved that a sizable amount of the byproduct ethanol was partitioned inside the inverse micelles. Characterization of the final product was carried out by means of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM), which concurrently confirmed that the silica isolated from the inverse nonionic microemulsion is not significantly different from the product of a bulk acid-catalyzed sol-gel synthesis. TEM micrographs illustrated particles with diameters smaller than the diameter of the inverse micelles as determined by SAXS, due to a shrinkage effect, in addition to nanostructured aggregates in the range 20-100 nm.
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Affiliation(s)
- F Asaro
- Department of Chemical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy.
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Abstract
An iridium anomaly has been found in coincidence with the known microtektite level in cores from Deep Sea Drilling Project site 149 in the Caribbean Sea. The iridium was probably not in the microtektites but deposited simultaneously with them; this could occur if the iridium was deposited from a dust cloud resulting from a bolide impact, as suggested for the anomaly associated with the Cretaceous-Tertiary boundary. Other workers have deduced that the microtektites are part of the North American strewn tektite field, which is dated at about 34 million years before present, and that the microtektite horizon in deep-sea cores is synchronous with the extinction of five radiolarian species. Mass extinctions also occur in terrestrial mammals within 4 million years of this time. The iridium anomaly and the tektites and microtektites are supportive of a major bolide impact about 34 million years ago.
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Abstract
Platinum metals are depleted in the earth's crust relative to their cosmic abundance; concentrations of these elements in deep-sea sediments may thus indicate influxes of extraterrestrial material. Deep-sea limestones exposed in Italy, Denmark, and New Zealand show iridium increases of about 30, 160, and 20 times, respectively, above the background level at precisely the time of the Cretaceous-Tertiary extinctions, 65 million years ago. Reasons are given to indicate that this iridium is of extraterrestrial origin, but did not come from a nearby supernova. A hypothesis is suggested which accounts for the extinctions and the iridium observations. Impact of a large earth-crossing asteroid would inject about 60 times the object's mass into the atmosphere as pulverized rock; a fraction of this dust would stay in the stratosphere for several years and be distributed worldwide. The resulting darkness would suppress photosynthesis, and the expected biological consequences match quite closely the extinctions observed in the paleontological record. One prediction of this hypothesis has been verified: the chemical composition of the boundary clay, which is thought to come from the stratospheric dust, is markedly different from that of clay mixed with the Cretaceous and Tertiary limestones, which are chemically similar to each other. Four different independent estimates of the diameter of the asteroid give values that lie in the range 10 +/- 4 kilometers.
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Abstract
Evidence indicates that the Cretaceous-Tertiary boundary is very sharp, and, within the limits of resolution, it is apparently synchronous at the various boundary localities. Arguments to the contrary, particularly those of Officer and Darke, are shown to invalid.
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Abstract
The present contribution aims at testing experimentally the theoretical model previously devised (Donati, I.; Cesaro, A.; Paoletti, S.; Biomacromolecules 2006, 7, 281-287) for the description of the interaction between alginate and nongelling Mg(2+) ions. The model, based on an extension of the counterion condensation theory, introduces a contribution of free energy of affinity, DeltaG(aff,0), which depends on the monomer composition of the polyuronate. In the present work, three different alginates separately mimicking the mannuronan (polyM), the guluronan (polyG), and the polyalternating (polyMG) components of alginate, together with a natural alginate isolated from Laminaria hyperborea ( L. hyperborea ), were examined. They were treated with Mg(2+) ions, and relative variations in scattered light intensity, isothermal calorimetry (DeltaH(mix)), specific viscosity, and (23)Na NMR longitudinal relaxation rates were monitored with respect to samples at the same ionic strength but containing only Na(+) ions. The fraction of condensed magnesium counterions was found to be strongly dependent on alginate composition, increasing along the series mannuronan < polyalternating approximately L. hyperborea < guluronan, thus in good agreement with the theoretical predictions.
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Affiliation(s)
- Ivan Donati
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, I-34127 Trieste, Italy.
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Asaro F, Benedetti A, Savko N, Pellizer G. Inverse nonionic microemulsion studied by means of 1H, 13C, and PGSTE NMR during silica nanoparticle synthesis. Langmuir 2009; 25:3224-3231. [PMID: 19437786 DOI: 10.1021/la803826c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The soluble species present in the reaction mixture that leads to silica nanoparticle production through the base catalyzed hydrolysis of tetraethyl orthosilicate (TEOS) and the successive condensation were investigated in situ, under the actual synthesis conditions, by means of 1H, 13C, and 29Si NMR spectroscopy. The two former nuclei, owing to higher sensitivity and their presence both in the reacting species and in the constituents of the W/O microemulsion (cyclohexane-igepal-CA-520-concentrated ammonia solution) afforded insight into the inverse microemulsion and allowed us to assess the kinetic rate of the hydrolysis step. It was verified that the microemulsion microstructure is maintained during the reaction. The characterization of the final nanoparticles was carried out by means of transmission electron microscopy (TEM). Special attention was paid to the reaction medium, and an extended assignment of the 1H and 13C resonances of the surfactant headgroup is reported together with the discussion of the changes they undergo due to the environmental modifications induced by transition from cyclohexane solution to W/O microemulsion and further to NH3 containing W/O microemulsion. The self-diffusion coefficient measurements revealed that NH3 exchanges among the inverse micelles diffusing through cyclohexane and confirmed that the preferred localization for ethanol, a byproduct of the reaction, is the bulk oil.
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Affiliation(s)
- Fioretta Asaro
- Department of Chemical Sciences, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy.
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Abstract
14N NMR spectra of air dissolved in lyotropic mesophases are reported. In order to observe the whole spectrum from a molecule in which the quadrupole coupling constant is on the order of a few megahertz, a weak alignment degree with respect to the magnetic field is mandatory. Therefore, dilute lyotropic liquid crystals, namely sodium dodecylsulphate (SDS)/pentanol swollen lamellar phases, were considered. The temperature dependence of the 14N quadrupolar splitting was followed both in the case of oil (either n-dodecane or n-heptane) and brine (a 0.2-M NaBr water solution) swelling. In the former, it paralleled the temperature dependence of the splittings of the alkane deuteria and, in both cases, it was opposite to 23Na quadrupolar splittings. Owing to the higher N2 solubility in hydrocarbons, the 14N NMR spectra provide complementary information to that obtained by means of the quadrupolar nuclei of water and hydrophilic solutes.
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Affiliation(s)
- Giorgio Pellizer
- Dipartimento di Scienze Chimiche, Università di Trieste, via L. Giorgieri 1, I-34127 Trieste, Italy.
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Orioni B, Roversi M, La Mesa C, Asaro F, Pellizer G, D'Errico G. Polymorphic Behavior in Protein−Surfactant Mixtures: The Water−Bovine Serum Albumin−Sodium Taurodeoxycholate System. J Phys Chem B 2006; 110:12129-40. [PMID: 16800527 DOI: 10.1021/jp055950r] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mixtures containing water, bovine serum albumin (BSA), and sodium taurodeoxycholate (NaTDC), a component of the bile in mammals, have been investigated in a wide range of composition and pH. Depending on the concentration of both solutes and the pH, solutions, precipitates, and gels are formed. Under spontaneous pH conditions, the transport properties in dilute solutions indicate the occurrence of significant interactions between BSA and the surfactant. Conversely, acidic media favor the formation of nonsoluble protein-surfactant complexes, with subsequent precipitation. The nucleation kinetics of the protein-surfactant complexes in solid form and the related precipitation processes can be slow or fast, depending on the overall solute content and the mole ratio. At high concentrations, a gel, extending on both sides of the charge neutralization line, and two-phase regions are observed. Gels shrink in open air and swell in the presence of excess water. Depending on concentration and temperature, the gels transform from an essentially liquidlike behavior to that peculiar to true gels (when G' > or = G''). The thermal gelation threshold, the temperature above which G' > or = G'', depends on BSA and NaTDC content and is concomitant to moderate heat effects, inferred by differential scanning calorimetry (DSC). The above data also indicate that the protein thermal denaturation in the gel is shifted to higher temperatures compared to water. Such a stabilizing effect is presumably related to the occurrence of both electrostatic and hydrophobic interactions with NaTDC. Water self-diffusion in the gels is slightly slower than that in the bulk and poorly sensitive to composition: it is about 65% the value of neat H2O in a wide concentration range, irrespective of the BSA, or NaTDC, concentration. A peculiar behavior is also observed in 23Na longitudinal and transverse relaxation rates. The T1 and T2 values, measured at 105.75 MHz on BSA-NaTDC gels, indicate that the motions determining the NMR relaxation of the sodium ions in the hydration layer of the protein-surfactant aggregates are not slow, having frequencies comparable with the Larmor one. The above properties, especially the rheological and the spectroscopic ones, are important for understanding the behavior of gels based on protein-surfactant mixtures.
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Affiliation(s)
- Barbara Orioni
- Dipartimento di Chimica and SOFT-INFM-CNR Research Center, Università La Sapienza, P.le A. Moro 5, 00185 Roma, Italy
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Galasso V, Asaro F, Berti F, Przybył A, Włodarczak J, Wysocka W, Habuš I, Kovač B. A combined spectroscopic and theoretical study of oxo- and thiono-sparteines. Chem Phys 2005. [DOI: 10.1016/j.chemphys.2005.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Pellizer G, Asaro F, Pergolese B. NMR investigations of Co(III) coordination compounds oriented in a dilute lyotropic liquid crystal. Magn Reson Chem 2004; 42:756-759. [PMID: 15307057 DOI: 10.1002/mrc.1420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A swollen lamellar phase, based on sodium dodecyl sulfate, pentanol and NaBr brine, was examined by means of NMR spectroscopy of isotopes with quadrupolar characteristics, namely 2H, 17O, 23Na and 81Br, present at natural abundance. Such a dilute lyotropic liquid crystal was capable of inducing a preferential orientation of the cobalt coordination compounds [Co(en)3]3+ and Co(acac)3, the 59Co NMR signals of which displayed quadrupolar splittings. Moreover, it imparted alignment in the magnetic field to the organocobaloxime [ClCD2Co(Hdmg)2H2O], as shown by the quadrupolar splitting of the deuterium of the axial ligand.
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Affiliation(s)
- Giorgio Pellizer
- Dipartimento di Scienze Chimiche, Università di Trieste, via L. Giorgieri 1, I-34127 Trieste, Italy.
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Bernazzani L, Borsacchi S, Catalano D, Gianni P, Mollica V, Vitelli M, Asaro F, Feruglio L. On the Interaction of Sodium Dodecyl Sulfate with Oligomers of Poly(Ethylene Glycol) in Aqueous Solution. J Phys Chem B 2004. [DOI: 10.1021/jp049673k] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luca Bernazzani
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Silvia Borsacchi
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Donata Catalano
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Paolo Gianni
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Vincenzo Mollica
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Matteo Vitelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Fioretta Asaro
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
| | - Luigi Feruglio
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35 − I-56126 Pisa, Italy, and Dipartimento di Chimica, Università di Trieste, Via L. Giorgeri 1-I-34127 Trieste, Italy
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Dreos R, Tauzher G, Geremia S, Randaccio L, Asaro F, Pellizer G, Tavagnacco C, Costa G. An Unusual Reaction of Bis(dimethylglyoximato) Complexes: Synthesis and Characterization of Rhodium(III) Complexes Containing an Oxime-Imine Equatorial Moiety. Inorg Chem 2002. [DOI: 10.1021/ic00102a011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Seaborg GT, Asaro F. Isadore Perlman: April 12, 1915-August 3, 1991. Biogr Mem Natl Acad Sci 2001; 75:265-87. [PMID: 11623761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Asaro F, Lenarda M, Pellizer G, Storaro L. A multinuclear NMR study of [Pt0(PPh3)2(alkene)] compounds containing asymmetric olefins. Spectrochim Acta A Mol Biomol Spectrosc 2000; 56A:2167-2175. [PMID: 11058062 DOI: 10.1016/s1386-1425(00)00278-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The 1H, 13C, 31P, and 195Pt NMR spectra of [Pt0(PPh3)2(eta-ABC(1) = C(2)XY)] compounds (ABC(1)= C(2)XY (1) A = B = X = Y = H; (3) A = B = X = H, Y = CN; (4) A = H, B = p-NO2-Ph, X = COOCH3, Y = CN; (5) A = H, B = Ph, X = COOCH3, Y = CN; (6) A = H, B = Ph, X = Y = CN; (7) A = H, B = OEt, X = Y = CN), where X and Y are electronacceptor substituents, and the 1H spectrum of [Pt0(PPh3)2(eta2-C60)] (2) are reported together with extended analyses and assignments, based also on the ring current effect of the olefin phenyl in (4-6). Deviations from first order in the 13C spectra allowed the determination of the relative signs of the coupling constants J(P(1), C) and J(P(2), C) of the alkene and of the triphenylphosphine carbons. Best fit simulation of the phosphine C ipso spectrum provided also the 13C isotopic shift on phosphorus for (1). These compounds are characterised by strong differences between the two platinum-phosphorus coupling constants in the case of asymmetric olefins (3-7). The chemical shifts of alkene C(1) and C(2) indicate notable polarisation of the olefin after complexation, while the 1J(Pt, C(1)) and 1J(Pt, C(2)) values are in agreement with a stronger interaction of Pt with C(1) than with C(2). These findings together with the trend of 195Pt chemical shifts confirm the important role played by back-donation in the bonding of platinum(0)-olefin compounds.
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Affiliation(s)
- F Asaro
- Dipartimento di Scienze Chimiche, Unirersità di Trieste, Italy.
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Asaro F, Liguori L, Pellizer G. Exceptional Deshielding of (59)Co Caused by Deuteration of the Hydrogen Bonds in Cobaloximes This work was supported by MURST under the Project Cofin (MURST 97 CFSIB). Angew Chem Int Ed Engl 2000; 39:1932-1934. [PMID: 10940985 DOI: 10.1002/1521-3773(20000602)39:11<1932::aid-anie1932>3.0.co;2-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- F Asaro
- Dipartimento di Scienze Chimiche Università di Trieste via L. Giorgieri 1, 34127 Trieste (Italy)
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Asaro F, Dreos* R, Nardin G, Pellizer G, Peressini S, Randaccio* L, Siega P, Tauzher G, Tavagnacco C. para-Substituted diphenylborylated organocobaloximes: effects of substituents on conformation and redox properties. J Organomet Chem 2000. [DOI: 10.1016/s0022-328x(00)00043-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Asaro F, Gobetto R, Liguori L, Pellizer G. Solution 31P and 59Co and solid-state 31P CP/MAS NMR studies of triphenylphosphinecobaloximes. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(98)01397-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Asaro F, Liguori L, Pellizer G. NMR parameters of cobalt and of the directly bonded organic carbons obtained from solution 59Co and 13C NMR spectra of cobaloximes. Phys Chem Chem Phys 1999. [DOI: 10.1039/a906376e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Asaro F, Camus A, Gobetto R, Olivieri AC, Pellizer G. 63Cu-31P coupling constants and 63Cu quadrupole couplings from 31P CP/MAS spectra of copper (I)--phosphine complexes with aryldithiocarboxylates or benzoate. Solid State Nucl Magn Reson 1997; 8:81-88. [PMID: 9203282 DOI: 10.1016/s0926-2040(96)01289-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Magic-angle spinning 31P NMR spectra of solid [CuS2C-Ph(PPh3)2] 1, [{CuS2C-pT}4(PPh3)2] 2, [{CuS2C-Ph}4(PPh3)2] 3. [CuS2C-Ph(dppm)]2 4 and [CuO2C-Ph(dppm)]2 5, (T = tolyl, dppm = bis(diphenylphosphino)methane) were obtained at 109.6 MH2. They consist of distorted quartets from non-equivalent phosphorus atoms and provide approximate values of the indirect spin-spin coupling constant J[63Cu,31P], that are indicative of the covalency of the dithiocarboxylate-copper bonding. The spacing distortions are related to a number of molecular and structural parameters and thereby allow an estimation of the copper quadrupole coupling constant e2qQ/h which, as expected, is smaller for tetra-coordinated (1, 2, 3 and 4) than for tri-coordinated (5) copper sites. The spectrum of 2 has been successfully simulated (including the isotope effects from the less abundant 65Cu isotope) using the full theory for calculation of the spin eigenfunctions of the quadrupolar nucleus.
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Affiliation(s)
- F Asaro
- Dipartimento di Scienze Chimiche, Università di Trieste, Italy
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Asaro F, Dreos R, Geremia S, Nardin G, Pellizer G, Randaccio L, Tauzher G, Vuano S. Synthesis, characterization and solution properties of organorhodium complexes derived from rhodoximes with one or two diphenylboron moieties in the oxime bridges. J Organomet Chem 1996. [DOI: 10.1016/s0022-328x(96)06479-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Asaro F, Costa G, Dreos R, Pellizer G, von Philipsborn W. Steric effects in organometallic compounds. A 103Rh NMR study of alkylrhodoximes. J Organomet Chem 1996. [DOI: 10.1016/0022-328x(95)06052-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kubiak M, Głowiak T, Moszner M, Ziółkowski JJ, Asaro F, Costa G, Pellizer G, Tavagnacco C. Synthesis and characterization of a novel tetranuclear bimetallic complex containing rhodium(II) and zinc(II) as metal centres. Inorganica Chim Acta 1995. [DOI: 10.1016/0020-1693(95)04637-o] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Mamolo MG, Vio L, Banfi E, Predominato M, Fabris C, Asaro F. Synthesis and antimycobacterial activity of some 4-pyridinecarboxyamidrazone derivatives. Farmaco 1993; 48:529-38. [PMID: 8357468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A series of N1-aryliden-4-pyridinecarboxyamidrazone derivatives was prepared. Some of the synthesized compounds showed interesting in vitro antimycobacterial activity against some strains of Mycobacterium and clinical isolates of Mycobacterium tuberculosis.
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Affiliation(s)
- M G Mamolo
- Dipartimento di Scienze Farmaceutiche, Facoltà di Farmacia, Università Degli Studi, Trieste, Italia
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