Browsing by Author "Lollo, Giovanna"
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- Fucoidan from Fucus Vesiculosus: Evaluation of the impact of the Sulphate content on Nanoparticle production and Cell toxicityPublication . FLÓREZ-FERNÁNDEZ, NOELIA; Pontes, Jorge Filipe; Guerreiro, Filipa; Afonso, Inês T.; Lollo, Giovanna; Torres, Maria Dolores; Domínguez, Herminia; M Rosa, Ana; Grenha, AnaThe composition of seaweeds is complex, with vitamins, phenolic compounds, minerals, and polysaccharides being some of the factions comprising their structure. The main polysaccharide in brown seaweeds is fucoidan, and several biological activities have been associated with its structure. Chitosan is another marine biopolymer that is very popular in the biomedical field, owing to its suitable features for formulating drug delivery systems and, particularly, particulate systems. In this work, the ability of fucoidan to produce nanoparticles was evaluated, testing different amounts of a polymer and using chitosan as a counterion. Nanoparticles of 200–300 nm were obtained when fucoidan prevailed in the formulation, which also resulted in negatively charged nanoparticles. Adjusting the pH of the reaction media to 4 did not affect the physicochemical characteristics of the nanoparticles. The IC50 of fucoidan was determined, in both HCT−116 and A549 cells, to be around 160 µg/mL, whereas it raised to 675–100 µg/mL when nanoparticles (fucoidan/chitosan = 2/1, w/w) were tested. These marine materials (fucoidan and chitosan) provided features suitable to formulate polymeric nanoparticles to use in biomedical applications.
- Nanocomposite sponges for enhancing intestinal residence time following oral administrationPublication . Rosso, Annalisa; Andretto, Valentina; Chevalier, Yves; Kryza, David; Sidi-Boumedine, Jacqueline; Grenha, Ana; Guerreiro, Filipa; Gharsallaoui, Adem; La Padula, Veronica; Montembault, Alexandra; David, Laurent; Briançon, Stéphanie; Lollo, GiovannaIn this work, nanocomposites that combine mucopenetrating and mucoadhesive properties in a single system are proposed as innovative strategy to increase drug residence time in the intestine following oral administration. To this aim, novel mucoadhesive chitosan (CH) sponges loaded with mucopenetrating nanoemulsions (NE) were developed via freeze-casting technique. The NE mucopenetration ability was determined studying the surface affinity and thermodynamic binding of the nanosystem with mucins. The ability of nanoparticles to penetrate across a preformed mucins layer was validated by 3D-time laps Confocal Laser Scanning Microscopy imaging. Microscopy observations (Scanning Electron Microscopy and Optical Microscopy) showed that NE participated in the structure of the sponge affecting its stability and in vitro release kinetics. When incubated with HCT 116 and Caco-2 cell lines, the NE proved to be cytocompatible over a wide concentration range. Finally, the in vivo biodistribution of the nanocomposite was evaluated after oral gavage in healthy mice. The intestinal retention of NE was highly enhanced when loaded in the sponge compared to the NE suspension. Overall, our results demonstrated that the developed nanocomposite sponge is a promising system for sustained drug intestinal delivery.
- Sulphated locust bean gum-coated lipid nanocapsules as potential lung delivery carriersPublication . Pontes, Jorge Filipe; Braz, L.; Guerreiro, Filipa; Rosa Da Costa, Ana; Almouazen, Eyad; Lollo, Giovanna; Grenha, AnaDrugs pertaining to Biopharmaceutics Classification System (BCS) classes II and IV have limitations in their delivery, including in the lung. Therefore, drug delivery carriers have been proposed to improve the therapeutic effectiveness of such drugs. This work proposes lipid nanocapsules (LNC) as a potential platform for lung drug delivery. Locust bean gum (LBG), which is a galactomannan, was used as polymeric shell, protecting the oily core of the nanocapsules and providing their surface with hydrophilic character. Due to the neutral character of LBG, in order to enable nanocapsule formation, a sulphate derivative (LBGS) was prepared, which was confirmed by Fourier-transformed infrared (FTIR) spectroscopy. The electrostatic interaction between the negatively charged sulphate groups of LBGS and the positively charged groups of the used cationic lipid (1,2-dioleoyloxy-3- trimethylammoniumpropanchloride, DOTAP), allowed the formation of monodisperse nanocapsules, with sizes around 200 nm and strongly negative zeta potentials, between -70 and -85 mV. Envisaging potential lung drug delivery, the LBGS-coated LNC were co-formulated with mannitol using spray-drying, producing microencapsulated nanocapsules. Feret’s diameter was determined to be 2.6 ± 1.8 µm and 3.1 ± 1.9 µm for Man (control) and Man/LNC microparticles, respectively. Further studies are underway in order to optimise both the nanoplatform and the dry powder formulation.
- Supersaturable self-microemulsifying delivery systems: an approach to enhance oral bioavailability of benzimidazole anticancer drugsPublication . Rosso, Annalisa; Almouazen, Eyad; Pontes, Jorge Filipe; Andretto, Valentina; Leroux, Marine; Romasko, Etienne; Azzouz-Maache, Samira; Bordes, Claire; Coste, Isabelle; Renno, Touffic; Giraud, Stephane; Briancon, Stephanie; Lollo, GiovannaThis study explored the design of supersaturable self-microemulsifying drug delivery systems (S-SMEDDS) to address poor solubility and oral bioavailability of a novel benzimidazole derivative anticancer drug (BI). Firstly, self-microemulsifying drug delivery systems SMEDDS made of Miglyol (R) 812, Kolliphor (R) RH40, Transcutol (R) HP, and ethanol were prepared and loaded with the BI drug. Upon dispersion, the systems formed neutrally charged droplets of around 20 nm. However, drug precipitation was observed following incubation with simulated gastric fluid (pH 1.2). Aiming at reducing this precipitation and enhancing drug payload, supersaturable systems were then prepared by adding 1% hydroxypropyl cellulose as precipitation inhibitor. Supersaturable systems maintained a higher amount of drug in a supersaturated state in gastric medium compared with conventional formulations and were stable in simulated intestinal medium ( pH 6.8). In vitro cell studies using Caco-2 cell line showed that these formulations reduced in a transient manner the transepithelial electrical resistance of the monolayers without toxicity. Accordingly, confocal images revealed that the systems accumulated at tight junctions after a 2 h exposure. In vivo pharmacokinetic studies carried out following oral administration of BI-loaded S-SMEDDS, SMEDDS, and free drug to healthy mice showed that supersaturable systems promoted drug absorption compared with the other formulations. Overall, these data highlight the potential of using the supersaturable approach as an alternative to conventional SMEDDS for improving oral systemic absorption of lipophilic drugs.