Search results for " micelles"

Chemical self-organization in self-assembling biomimetic systems

2009

Abstract Far-from-equillibrium oscillating chemical reactions are among the simplest systems showing complex behaviors and emergent properties. This class of reactions is often employed to mimic and understand the mechanisms of a great variety of biological processes. In this context, pattern formation due to the coupling between reaction and transport phenomena represent an active and promising research area. In this paper, we present results coming from experiments where we tried to blend the structural properties of self-assembled matrixes (sodium dodecyl sulphate micelles and phospholipid bilayers) together with the evolutive peculiarities of the Belousov–Zhabotinsky reaction. A series …

Morphology of hybrid polystyrene-block-poly(ethylene oxide) micelles: Analytical ultracentrifugation and SANS studies

2006

Abstract Morphology and structure of aqueous block copolymer solutions based on polystyrene- block -poly(ethylene oxide) (PS- b -PEO) of two different compositions, a cationic surfactant, cetyl pyridinium chloride (CPC), and either platinic acid (H 2 PtCl 6 ⋅6H 2 O) or Pt nanoparticles were studied using a combination of analytical ultracentrifugation (AUC), transmission electron microscopy (TEM), and small angle neutron scattering (SANS). These studies combining methods contributing supplemental and analogous structural information allowed us to comprehensively characterize the complex hybrid systems and to discover an isotope effect when H 2 O was replaced with D 2 O. In particular, TEM s…

Antimicrobial Peptides and Their Superior Fluorinated Analogues: Structure-Activity Relationships as Revealed by NMR Spectroscopy and MD Calculations

2010

9 pag., 6 fig, 3 tab.

Galactosylated polymeric carriers for liver targeting of sorafenib

2014

In this paper, we describe the preparation of liver-targeted polymeric micelles potentially able to carry sorafenib to hepatocytes for treatment of hepatocarcinoma (HCC), exploiting the presence of carbohydrate receptors, ASGPR. These micelles were prepared starting from a galactosylated polylactide-polyaminoacid conjugate. This latter was obtained by chemical reaction of α,β-poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-d,l-aspartamide (PHEA-EDA) with polylactic acid (PLA), and subsequent reaction with lactose, leading to PHEA-EDA-PLA-GAL copolymer. Liver-targeted sorafenib-loaded micelles were obtained in aqueous media at low PHEA-EDA-PLA-GAL copolymer concentration value with nanometer …

About entangled networks of worm-like micelles: a rejected hypothesis

1996

We report new results from small-angle neutron scattering on d(1 2)-cyclohexane/lecithin/water micellar solutions performed as a function of the water content (w(o)), temperature (T) and dispersed phase volume fraction (phi). The data from dilute samples are interpretable in terms of the existence of giant cylindrical reverse micelles and are well fit with a core-shell model (that provides the micelle structure and dimensions) with values of 28 and 45 Angstrom for the inner core and the outer shell radii, almost independent on temperature and concentration. Such a result could appear consistent with the current idea that worm-like micelles are living polymers. On the contrary, the appearanc…

STRATEGIE DI DIREZIONAMENTO ALL’EPATOCARCINOMA DI FARMACI ANTITUMORALI MEDIANTE SISTEMI NANOPARTICELLARI E DI VISUALIZZAZIONE IN CELLULE TUMORALI DEL…

Lo scopo di questo lavoro di tesi è stato quello di realizzare nuovi sistemi nanoparticellari per il direzionamento di farmaci o di agenti per l’imaging, potenzialmente utilizzabili per la terapia e/o per la diagnosi dell’epatocarcinoma (HCC), in particolare per quelle forme caratterizzate dall’overespressione del recettore di membrana degli epatociti ASGP-R o del recettore mitocondriale TSPO. In particolare, nel capitolo 2 sono state descritte la sintesi, la caratterizzazione chimico fisica, la capacità di internalizzazione cellulare e l’efficacia antitumorale di un nuovo sistema nanoparticellare, costituito da un dendrimero a struttura poli-amido-aminica (PAMAM) di quarta generazione, opp…

SMOOTHLY SHIFTING FLUORESCENT WINDOW: TUNABLE “OFF-ON-OFF” MICELLAR BIOSENSORS FOR pH

2009

Complex permittivity of FeCl3/AOT/CCl4 microemulsions probed by AC impedance spectroscopy

2009

Abstract The complex permittivity of FeCl 3 /AOT/CCl 4 microemulsions in the 1–10 5  Hz frequency range has been measured by the conventional AC complex impedance technique. Measurements as a function of the volume fraction of the dispersed phase (FeCl 3  + AOT) and temperature at fixed salt-to-AOT molar ratio ( R , R  = 0.5) show that the entrapment of FeCl 3 clusters significantly enhances the local permittivity of the AOT reverse micelles and the number density of charge carriers resulting from the peculiar state of the confined inorganic salt. An estimate of the apparent static permittivity of the FeCl 3 ionic clusters entrapped in the core of AOT reverse micelles gives the very high an…

MICELLES OF AMPHYPHLIC HYALURONIC ACID DERIVATIVES FOR TARGETED DELIVERY OF DOXORUBICIN

2009

MICELLE POLIMERICHE A BASE DI NUOVI DERIVATI ANFIFILICI DELL’INULINA PER LA SOMMINISTRAZIONE OCULARE TOPICA DI CORTICOSTEROIDI NEL TRATTAMENTO DELLE …

2016

Al giorno d’oggi, la via di somministrazione oftalmica costituisce ancora una sfida per i tecnologi farmaceutici. Si tratta, inoltre, probabilmente di uno degli ambiti che più di ogni altro potrebbe beneficiare dello sviluppo di nuovi Drug Delivery Systems basati sull’utilizzo di nanovettori. Infatti, più del 50% delle patologie oculari maggiormente debilitanti (es. degenerazione maculare legata all’età, retinopatia diabetica ed edema maculare diabetico) ha origine a livello del segmento oculare posteriore. Ad oggi, la terapia intravitreale costituisce il gold standard per garantire il raggiungimento del sito target, ovvero la retina. Tuttavia, la necessità di ricorrere a frequenti somminis…