Here, long-circulating behaviors of Inulin-based nanomicelles are demonstrated for the first time in vivo. We show the synthesis and evaluation of biotin (BIO)-decorated polymeric INVITE micelles constituted of substances of natural origin, Inulin (INU) and Vitamin E (VITE), as long-circulating carriers for receptor-mediated targeted drug delivery. The resulting INVITE or INVITE-BIO micelles, nanometrically sized, did not reveal any cytotoxicity after 24h of incubation with Caco-2 cells. Moreover, in vitro studies on Caco-2 cells monolayers indicated that the transport of INVITE-BIO micelles was faster than surface unmodified INVITE micelles. In vivo optical imaging studies evidenced that, upon intravenous administration, INVITE-BIO micelles were quantitatively present in the body up to 48h. Instead, after oral administration, the micelles were not found in the systemic circulation but eliminated with the normal intestinal content. In conclusion, INVITE-BIO micelles may enhance drug accumulation in tumor-cells over-expressing the receptor for biotin through receptor mediated endocytosis.

Objectives: Drug-eluting degradable polymers represent a new direction in vascular surgery. Subcutaneous implantation in rats of vascular prostheses is a rapid and cost-effective screening model to assess the drug-elution effect and could to some extent be extrapolated to forecast results for vascular implantation. We therefore assessed the biologic and histologic response according to the implantation site. Materials & Methods: Polycaprolactone(PCL), paclitaxel-loaded PCL(PCL-PTX) and dexamethasone-loaded PCL(PCL-DXM) grafts were implanted subcutaneously(n=60) and in an infrarenal abdominal aortic replacement model(n=28) in rats for 1,3 and 12 weeks. At conclusion of the study histological analysis was performed in all groups and models. Results: Cellular graft invasion was analyzed by morphometry in the subcutaneous and aortic group revealing time differences of infiltration between PCL, PCL-PTX and PCL-DXM groups in both models. Cell infiltration was continuously increasing with time in the aortic model compared to the subcutaneous model(41% vs. 28% at 12 weeks). Morphological cell counting revealed major differences in fibroblast, macrophage and giant cell graft colonisation with time. Macrophages and giant cells increased more in the aortic compared to the subcutaneous model after 3 weeks but decreased in the drug-eluting groups. Other major findings were observed only in the aortic replacement such as extracellular matrix deposition and neo-angiogenesis. Conclusions: The subcutaneous polymer implant model can be used for screening, especially when drug-eluting effects are studied. However major histological differences are observed in cell type reaction and depth of cell penetration compared to the aortic replacement model. Thus our results demonstrate that no extrapolations should be made from a subcutaneous screening to a vascular implantation model.

The main aim of the present study was to estimate the carrier characteristics affecting the dissolution efficiency of Griseofulvin (Gris) containing blends (BLs) using partial least squares (PLS) regression analysis. These systems were prepared at three different drug/carrier weight ratios (1/5, 1/10, and 1/20) by the solvent evaporation method, a well-established method for preparing solid dispersions (SDs). The carriers used were structurally different including polymers, a polyol, acids, bases and sugars. The BLs were characterised at the solid-state by spectroscopic (Fourier transform infrared spectroscopy), thermoanalytical (differential scanning calorimetry) and X-ray diffraction studies and their dissolution behaviours were quantified in terms of dissolution efficiencies (log DE/DEGris). The correlation between the selected descriptors, including parameters for size, lipophilicity, cohesive energy density, and hydrogen bonding capacity and log DE/DEGris (i.e., DE and DEGris are the dissolution efficiencies of the BLs and the pure drug, respectively) was established by PLS regression analysis. Thus two models characterised by satisfactory coefficient of determination were derived. The generated equations point out that aqueous solubility, density, lipophilic/hydrophilic character, dispersive/polar forces and hydrogen bonding acceptor/donor ability of the carrier are important features for dissolution efficiency enhancement. Finally, it could be concluded that the correlations developed may be used to predict at a semiquantitative level the dissolution behaviour of BLs of other essentially neutral drugs possessing hydrogen bonding acceptor groups only.

Drug-eluting vascular prostheses represent a new direction in vascular surgery to reduce early thrombosis and late intimal hyperplasia for small calibre grafts. Subcutaneous implantation in rats is a rapid and cost-effective screening model to assess the drug-elution effect and could, to some extent, be useful to forecast results for vascular prostheses. We compared biological and histological responses to scaffolds in different implantation sites. Polycaprolactone (PCL), paclitaxel-loaded PCL (PCL-PTX) and dexamethasone-loaded PCL (PCL-DXM) electrospun scaffolds were implanted subcutaneously and in an infrarenal abdominal aortic model in rats for up to 12 weeks. At the conclusion of the study, a histological analysis was performed. Cellular graft invasion revealed differences in the progression of cellular infiltration between PCL-PTX and PCL/PCL-DXM groups in both models. Cell infiltration increased over time in the aortic model compared to the subcutaneous model for all groups. Cell counting revealed major differences in fibroblast, macrophage and giant cell graft colonisation in all groups and models over time. Macrophages and giant cells increased in the PCL aortic model; whereas in the subcutaneous model these cell types increased only after three weeks or even decreased in the drug-eluting PCL groups. Other major findings were observed only in the aortic replacement such as extracellular matrix deposition and neo-angiogenesis. The subcutaneous implant model can be used for screening, especially when drug-eluting effects are studied. However, major histological differences were observed in cell type reaction and depth of cell penetration compared to the aortic model. Our results demonstrate that the implantation site is a critical determinant of the biological response.

Hyaluronic acid (HA) is a biodegradable, biocompatible, nontoxic, and non-immunogenic glycosaminoglycan used for various biomedical applications. The interaction of HA with the CD44 receptor, whose expression is elevated on the surface of many types of tumor cells, makes this polymer a promising candidate for intracellular delivery of imaging and anticancer agents exploiting a receptor-mediated active targeting strategy. Therefore, HA and its derivatives have been most investigated for the development of several carrier systems intended for cancer diagnosis and therapy. Nonetheless, different and important delivery applications of the polysaccharide have also been described, including gene and peptide/protein drugs delivery. The aim of this review was to provide an overview of the existing recent literature on the use of HA and its derivatives for drug delivery and imaging. Notable attention is given to nanotheranostic systems obtained after conjugation of HA to nanocarriers as quantum dots, carbon nanotubes and graphene. Meanwhile, attention is also paid to some challenging aspects that need to be addressed in order to allow translation of preclinical models based on HA and its derivatives for drug delivery and imaging purposes to clinical testing and further their development.

The primary aim of the present work was to evaluate the in vitro uptake of 6-Coumarin (6COUM) loaded solid lipid nanoparticles (SLN) by two gilthead seabream (Sparus aurata L.) cell types: an established cell line (SAF-1 cells) and the primary cultures of head-kidney (HK)—the main haemopoietic organ in fish, equivalent to mammalian bone marrow—leucocytes. For this purpose, after the physicochemical characterization of SLN, the uptake by those immunocompetent fish cells was evaluated using flow cytometry and confocal microscopy. Concomitantly, the uptake of 6-COUM loaded SLN was compared with that achieved with 6-COUM loaded pectin microparticles (MPs), which were selected as a competitor of the delivery carriers. After SLN and MP physicochemical characterization, the results demonstrated that SAF-1 cells were able to internalize high percentages of 6-COUM SLNs when incubated for 4, 8 and 24 h, with the highest SLN concentration tested (10 μg/ml). The ability of HK leucocytes to internalize SLN was also found to vary depending on both incubation time and SLN concentration. The highest values of HK leucocytes internalizing SLN particles (around 16%) were detected at the maximum SLN concentration (20 μg/ml) at incubation times of 4 or 8 h. Conversely, HK leucocytes were unable to internalize MPs at any tested concentration and incubation time. A possible mechanism explaining the uptake into cells is proposed. The present work constitutes the first approximation to consider SLN as nanocarriers for delivering biologically active substances to fish.

The aim of this study was to evaluate chitosan (CS)-, glycol chitosan (GCS)- and corresponding thiomer-based nanoparticles (NPs) for delivering dopamine (DA) to the brain by nasal route. Thus, the polyanions tripolyphosphate and sulfobutylether-β-cyclodextrin (SBE-β-CD), respectively, were used as polycation crosslinking agents and SBE-β-CD also in order to enhance the DA stability. The most interesting formulation, containing GCS and SBE-β-CD, was denoted as DA GCS/DA-CD NPs. NMR spectroscopy demonstrated an inclusion complex formation between SBE-β-CD and DA. X-ray photoelectron spectroscopy analysis revealed the presence of DA on the external surface of NPs. DA GCS/DA-CD NPs showed cytotoxic effect toward Olfactory Ensheathing Cells only at higher dosage. Acute administration of DA GCS/DA-CD NPs into the right nostril of rats did not modify the levels of the neurotransmitter in both right and left striatum. Conversely, repeated intranasal administration of DA GCS/DA-CD NPs into the right nostril significantly increased DA in the ipsilateral striatum. Fluorescent microscopy of olfactory bulb after acute administration of DA fluorescent-labeled GCS/DA-CD NPs into the right nostril showed the presence of NPs only in the right olfactory bulb and no morphological tissue damage occurred. Thus, these GCS based NPs could be potentially used as carriers for nose-to-brain DA delivery for the Parkinson's disease treatment.

The aim of this work was to evaluate the potential of INVITE-based nanomicelles, an amphiphilic polymer constituted by inulin (INU) and vitamin E (VITE), as a platform for improving the biopharmaceutical properties of hydrophobic drugs. For this purpose, curcumin was selected as a model and curcumin-INVITE nanomicelles were prepared. This drug delivery system was characterized both in vitro for what concerns the physicochemical properties, blood compatibility, and cellular uptake, and in vivo for the evaluation of the pharmacokinetic profile. It was found that these nanomicelles released curcumin in a controlled manner, and they were able to penetrate cellular membrane. Moreover, they showed an improved pharmacokinetic profile after intravenous administration. In conclusion, INVITE micelles might constitute promising nanocarriers for improving the biopharmaceutical performance of hydrophobic drugs.

In this work the hydrophobic core of Inulin based micelles has been exploited for the loading of the model hydrophobic drug curcumin (solubility 11ng/ml), the drug release studies have been performed in simulated physiological fluids. Furthermore, biological studies on suitable cell lines have been performed to verify the biocompatibility of INVITE conjugates.

New conjugates between inulin (INU) and vitamin E (VITE) able to form amphiphilic systems self-assembling in nanostructures thought for biomedical applications such as the therapy of urinary tract affections were prepared. This work, shows the syntheses, characterization and self-assembling properties of the obtained polymeric conjugates (INVITE). The reaction between VITE and INU has been carried out in bulk, without isolation of intermediate products leading to a convenient one-step reaction. To tailor the physical-chemical characteristics of the INVITE bioconjugate, six different INVITE conjugates were obtained by varying the relative amount of bonded VITE respect to INU repeating units. The obtained products were characterized by 1H-NMR, 13C-NMR, FT-IR and DSC. Furthermore, to verify that VITE does not undergo any oxidation during the reactions, UV-VIS analyses have been performed and the ability of the new conjugates to form nanoparticulate systems in water or 0.9 % saline was performed by dynamic light scattering. Furthermore, in the same media, was evaluated the stability of the INVITE nanosystems after incubation at 25 °C up to 12 days, by measuring at different time points their size variation. The degree of derivatization was found not influenced by the temperature, but it mostly depend from the different molar ratios. Interestingly, the introduction of VITE in the inulin backbone resulted almost quantitative. All conjugates resulted self-assembling in water forming nanosystems sized below 100 nm. The nanosystems are stable and do not aggregate after 12 days incubation. These results strongly encourage to prove these systems for drug delivery applications.

Aim of this project is the synthesis and characterization of nanostructured drug delivery systems (DDS) to be used in the therapy of urinary tract affections. The main idea is based on the synthesis of a bioconjugate between inulin and vitamin E (INVITE) able to produce amphiphilic systems self-assembling in nanostructured DDS even at low concentrations. A so ideated system should solubilize, incorporate and protect lipophilic drugs while targeting them in the urinary tract [1,2].