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Glaucoma and other optic neuropathies are characterized by a loss of retinal ganglion cells (RGCs), a cell layer located in the posterior eye segment. Several preclinical studies demonstrate that neurotrophins (NTs) prevent RGC loss. However, NTs are rarely investigated in the clinic due to various issues, such as difficulties in reaching the retina, the very short half-life of NTs, and the need for multiple injections. We demonstrate that NTs can be conjugated to magnetic nanoparticles (MNPs), which act as smart drug carriers. This combines the advantages of the self-localization of the drug in the retina and drug protection from fast degradation. We tested the nerve growth factor and brain-derived neurotrophic factor by comparing the neuroprotection of free versus conjugated proteins in a model of RGC loss induced by oxidative stress. Histological data demonstrated that the conjugated proteins totally prevented RGC loss, in sharp contrast to the equivalent dose of free proteins, which had no effect. The overall data suggest that the nanoscale MNP-protein hybrid is an excellent tool in implementing ocular drug delivery strategies for neuroprotection and therapy. [ABSTRACT FROM AUTHOR]

In this article, a carbon nanotube (CNT) array-based system combined with a polymer thin film is proposed as an effective drug release device directly at cellular level. The polymeric film embedded in the CNT array is described and characterized in terms of release kinetics, while in vitro assays on PC12 cell line have been performed in order to assess the efficiency and functionality of the entrapped agent (neural growth factor, NGF). PC12 cell differentiation, following incubation on the CNT array embedding the alginate delivery film, demonstrated the effectiveness of the proposed solution. The achieved results indicate that polymeric technology could be efficiently embedded in CNT array acting as drug delivery system at cellular level. The implication of this study opens several perspectives in particular in the field of neurointerfaces, combining several functions into a single platform. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is increasingly being used in the treatment of several aggressive cancers, including cerebral glioblastoma multiforme. The main requirement for this therapy is selective targeting of tumor cells by sufficient quantities of 10B atoms required for their capture/irradiation with low-energy thermal neutrons. The low content of boron targeting species in glioblastoma multiforme accounts for the difficulty in selective targeting of this very malignant cerebral tumor by this radiation modality. In the present study, we have used for the first time boron nitride nanotubes as carriers of boron atoms to overcome this problem and enhance the selective targeting and ablative efficacy of BNCT for these tumors. Following their dispersion in aqueous solution by noncovalent coating with biocompatible poly- l-lysine solutions, boron nitride nanotubes were functionalized with a fluorescent probe (quantum dots) to enable their tracking and with folic acid as selective tumor targeting ligand. Initial in vitro studies have confirmed substantive and selective uptake of these nanovectors by glioblastoma multiforme cells, an observation which confirms their potential clinical application for BNCT therapy for these malignant cerebral tumors. [ABSTRACT FROM AUTHOR]

Despite the higher rate of blindness due to population aging, minimally invasive and selective drug delivery to the eye still remains an open challenge, especially in the posterior segment. The retina, the retinal pigment epithelium (RPE) and the choroid are posterior segment cell layers, which may be affected by several diseases. In particular, damages to the choroid are associated with poor prognosis in the most severe pathologies. A drug delivery approach, able to target the choroid, is still missing. Recently, we demonstrated that intravitreally injected magnetic nanoparticles (MNP) are able to rapidly and persistently localise within the RPE in an autonomous manner. In this work we functionalised the MNP surface with the vascular endothelial growth factor, a bioactive molecule capable of transcytosis from the RPE towards more posterior layers. Such functionalisation successfully addressed the MNPs to the choroid, while MNP functionalised with a control polypeptide (poly-L-lysine) showed the same localisation pattern of the naked MNP particles. These data suggest that the combination of MNP with different bioactive molecules could represent a powerful strategy for cell-specific targeting of the eye posterior segment. [ABSTRACT FROM AUTHOR]