Elvira Avallone

C2-symmetrical sterol–polyether conjugates as highly efficient synthetic ionophores

A new class of artificial ionophores has been rationally designed and synthesized linking to a tetrafunctionalized l-treitol spacer two rigid hydrophobic 3β-hydroxy-5α-23,24-bisnorcholanic units and two flexible hydrophilic oligo(ethylene glycol) chains. Compounds 1a and 1b were incorporated into phospholipid vesicles and shown to facilitate Na+-transport.

Preparation and characterization of biodegradable active PLA film for food packaging

In this work we report on the preparation and characterization of a biodegradable active PLA film (aPLA), intended for food packaging applications. The film was obtained by cast extrusion blending a commercial PLA matrix with an active system, developed in our laboratory and based on PLA microparticles containing a-tocopherol (aTCP) as natural antioxidant agent. In order to optimize the film composition and processing, the active microparticles were preliminarily characterized with the aim to evaluate their morphology (size and shape), thermal resistance and a-tocopherol content. The aPLA film, produced with a 5wt% of aTCP, was characterized in terms of performance and activity. The experimental results demonstrated that the aPLA film has mechanical, thermal, barrier and optical properties adequate for packaging applications and shows oxygen scavenging activity and prolonged exhaustion lag time, compared to pure PLA films.

Optical and mechanical properties of UV-weathered biodegradable PHBV/PBAT nanocomposite films containing halloysite nanotubes

Recently, the increasing use of plastics, stringent environmental issues and the awareness of the progressive reduction of available petrochemical resources have ever more guided the research interest towards the investigation and development of innovative materials intrinsically biodegradable or derived from renewable sources, and generally known as bio-based polymers. Amongst the biobased and biodegradable polymers, many investigations were reported in literature about a family of polyesters known as poly(hydroxyalkanoate)s (PHAs), one of whose most prevalent is poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). In this context, here we report the results of a photo-degradation study performed on biodegradable blown film samples based on a commercial grade PHBV/PBAT formulation. The films, subjected to photo-oxidative weathering in a climatic chamber under UV exposure, were systematically analysed in order to check the chemico-physical changes induced by the aging protocol, taking the as-produced film...

MORPHOLOGY AND DRUG RELEASE OF PH‐SENSITIVE MICROSPHERES CONTAINING FLAVONOIDS

In this work we developed pH‐sensitive microspherical dosage forms for poorly water soluble flavonoids (quercetin and naringenin) by using Eudragit L100 as enteric polymer. The systems were produced by water in oil (w/o) solvent evaporation method, optimizing the formulation and preparation conditions in order to obtain high encapsulation efficiency and production yield. The synthesized microspheres were characterized in terms of particle size distribution, drug loading, morphology and in vitro release properties. The performed analyses evidenced that the microspheres were free‐ flowing and spherical in shape, both quercetin and naringenin were microencapsulated in the amorphous state and the drug content was near to the theoretical one. Preliminary in vitro dissolution studies, carried out using a pH‐change method, showed that the samples exhibit a typical biphasic drug release trend, due to the pH dependent solubility of the enteric polymers used. In particular, the samples have a fairly gastroresistanc...