730 research outputs found
Emerging technologies in solid drug delivery: An interview with Nadia Passerini
No full textNadia Passerini is interviewed by Hannah Makin, Commission Editor. Nadia Passerini is Associate Professor of Pharmaceutical Technology at the University of Bologna (Bologna, Italy). She obtained the degree in Pharmaceutical Chemistry and Technology at the University of Bologna in 1992 and the PhD in Pharmaceutical Science in 1997. Her research focuses on the study of drug delivery systems, developing new technologies and new apparatus for the production of solid dosage forms (microparticles, granules and tablets), which can optimize the bioavailability of drugs according to the specific needs of the therapy. Furthermore, she is interested in the solid-state characterization of the produced delivery systems in order to correlate their physicochemical properties to the in vitro release of the drugs. Currently, her research focuses in particular on the production and characterization of microparticles produced by the spray congealing technology. She is author of over 50 international peer-reviewed publications and over 50 contributions (poster and oral presentations) to national and international conferences
Memories Between Silence and Oblivion
No full textThe article is dedicated to a certain issue crucial for understanding the shaping of collective memory in the 20th century – the mechanisms creating areas of “collective oblivion” and the actions of restoring what has been removed from memory, repressed, omitted or kept secret. The studies and papers recalled in the erudite sketch go far beyond the borders of European memories, giving the readers an insight into the phenomena of memory and silence in their global dimension. By doing so, Luisa Passerini encourages her readers to abandon the arrogant belief in our uniqueness and cultural superiority.
[Translation based on: L. Passerini, “Memories Between Silence and Oblivion”, [in:] Memory and Utopia. The Primacy and Intersubjectivity, London–New York 2007, p. 15–32. The permission to publish the translated version of the article has been granted by the author. License: CC BY-SA 4.0. (editor’s note)
Polymers of lignin-sourced components as a facile chemical integrant for the Passerini three-component reaction
No full textPoly(methacrylated vanillin) (PMV) was investigated for its reactivity in multicomponent reactions as a reactive polymer that can be sourced from lignin-based components. To achieve sustainable polymer chemistry, the PMV reactivity in a Passerini three-component reaction (Passerini-3CR) was investigated because the reactants in the Passerini-3CR can be abundantly sourced from biobased compounds. First, the Passerini-3CR of the PMV in solution phases revealed that the PMV pendant aldehydes can be converted into the corresponding α-acyloxy amides with >90% conversions under the optimized conditions. Taking advantage of this high reactivity of PMV, its immobilized cellulose fabric (Cell-g-PMV), a wood biomass-sourced organic hybrid, was subjected to the Passerini-3CR. Although the aldehydes were not completely converted, the PMV segments surrounding the fabric surfaces successfully reacted via the Passerini-3CR to engraft carboxylic acid and isocyanide components on the cellulose-based fabrics.journal articl
Artificial macrocycles by Ugi reaction and Passerini ring closure
No full textArtificial macrocycles can be convergently synthesized by a sequence of an Ugi multicomponent reaction (MCR) followed by an intramolecular Passerini MCR used to close the macrocycle. Significantly, in this work, the first intramolecular macrocyclization through a Passerini reaction is described. We describe 21 macrocycles of a size of 15-20. The resulting macrocyclic depsipeptides are model compounds for natural products and could find applications in drug discovery
Hydrophobization of carboxymethyl cellulose by Passerini reaction: towards films with improved water vapor barrier properties
No full textInternational audienceTo address the need for developing sustainable materials with effective barriers to water vapor, this work explores the potential of self-supported films made of carboxymethyl cellulose (CMC) functionalized by the Passerini three-component reaction. Aliphatic aldehydes and tert-butyl isocyanide were grafted onto CMC backbone to yield dually hydrophobized derivatives. These modified polysaccharides were processed into films by solvent casting and their water vapor transfer properties were examined. Small-angle X-ray scattering (SAXS) experiments revealed a nanoscale organization for Passerini-modified films, attributed to the formation of hydrophobic domains characterized by a nanometric interdomain spacing. Dynamic vapor sorption (DVS) analysis demonstrated a significant reduction in moisture content water for modified films, from ≃ 1.1 g g -1 for unmodified CMC to below 0.5 g g -1 for hydrophobized derivatives at a w = 0.95. Guggenheim-Anderson-deBoer (GAB) and Zimm-Lundberg modeling showed a decrease in sorption site availability from 3 to ≃ 1.5 per glucose unit, while the size of water clusters was significantly increased. The Passerini modification also resulted in a substantial decrease of water vapor permeability (WVP) from 44 000 barrer to 2500 barrer at a w = 0.5. These results unequivocally underpin the benefits of the Passerini functionalization which allows to enhance the water vapor barrier performance. The findings highlight the potential of such a reaction for developing next-generation and bio-based packaging materials with tailored water vapor barrier properties.</div
La città della creatività
No full textDa sempre metropoli pilota dello sviluppo economico italiano, Milano ha attraversato profonde trasformazioni negli ultimi decenni diventando da capitale dell'industria, capitale dei servizi, della creatività e dell'innovazione. Da vertice del famoso e ormai dimenticato "triangolo industriale" a capitale mondiale del design e della moda. Milano può essere definita il laboratorio dell'innovazione nel lavoro e nelle professioni, in cui avvengono e si manifestano fenomeni che poi vengono diffusi nel resto del paese. È in questo passato e in questo presente che possiamo rintracciare le ragioni di questo libro su Milano, città del lavoro. Lavoro qui scandagliato nelle sue dimensioni simbolico-rappresentative (letteratura e cinema), nei cambiamenti sociologici, nello sviluppo tecnologico, nella prospettiva storica del superamento della grande industria e al contempo della quasi sotterranea, ma vitalissima continuità del lavoro artigiano. Un libro che raccoglie un gruppo di agili saggi di ordine generale e una serie di schede sui "nuovi lavori" che animano la scena cittadina. A due importanti reportage fotografici è invece affidato il compito di comunicare visivamente il modo di lavorare dei milanesi di oggi nel coesistere di lavori vecchi e nuovi o ancora di lavori tradizionali rivisitati con l'applicazione di nuove tecnologie e di nuove forme di organizzazione. Non manca anche uno sguardo sul passato e sui luoghi "monumentali" dell'industria milanese recuperati a nuovi usi produttivi e non
An investigation into the effects of residual water on the glass transition temperature of polylactide microspheres using modulated temperature DSC
No full textThe objective of the study was to ascertain residual water levels in polylactide and polylactide-co-glycolide microspheres prepared using the solvent evaporation technique and to investigate the effects of that water on the glass transitional behaviour of the microspheres. Microspheres were prepared from polylactic acid (PLA) and polylactide-co-glycolide (PLGA) 50:50 and 75:25 using a standard solvent evaporation technique. The glass transition was measured as a function of drying conditions using modulated temperature DSC. The microspheres were found to contain very low levels of dichloromethane, while residual water levels of up to circa 3% w/w were noted after freeze or oven drying, these levels being higher for microspheres containing higher glycolic acid levels. The residual water was found to lower the Tg following the Gordon–Taylor relationship. The data indicate that the microparticles may retain significant water levels following standard preparation and drying protocols and that this drying may markedly lower the Tg of the spheres
MetalDetector v2.0: Predicting the geometry of metal binding sites from protein sequence
No full textMetalDetector identifies CYS and HIS involved in transition metal protein binding sites, starting from sequence alone. A major new feature of release 2.0 is the ability to predict which residues are jointly involved in the coordination of the same metal ion. The server is available at http://metaldetector.dsi.unifi.it/v2.0/. © 2011 The Author(s)
Facile synthesis of photo-cleavable polymers via Passerini reaction
No full textPasserini three-component reaction and multicomponent polymerization (MCP) were demonstrated to be facile methods for the preparation of photo-cleavable polymers, photo- and redox-dually cleavable polymers, as well as block copolymers.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000323726600039&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Chemistry, MultidisciplinarySCI(E)35ARTICLE768549-85514
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