Silicon dioxide surfaces, both bulk and porous, were used to anchor the enzyme glucose oxidase. The immobilization protocol was optimized and the samples characterized using X-ray Photoelectron Spectroscopy, Energy Dispersive X-rays coupled to scanning electron microscopy and enzymatic activity measurements. We show that a uniform layer was obtained by activating the oxide before immobilization. X-ray Photoelectron Spectroscopy measurements carried out on bulk oxide showed that the silicon substrate signal was fully screened after the enzyme deposition showing the absence of uncovered surface regions. The enzyme presence was detected monitoring both the C 1s and N 1s signals. Finally, enzymatic activity measurements confirmed that the glucose oxidase activity was preserved after immobilization and maintained after three months of shelf life if the sample was properly stored. The importance of using porous silicon oxide to maximize the surface area was also evidenced.

Biomolecule immobilization on bulk silicon dioxide (SiO₂) is an important aspect in the field of Si-based interfaces for biosensing. The approach used for surface preparation should guarantee not only the stable anchoring of biomolecules but also their structural integrity and biological functioning. In this paper, we review our findings on the SiO₂ functionalization process to immobilize a variety of biomolecules, including glucose oxidase, horseradish peroxide, metallothionein, and DNA molecules. Morphological and chemical characterization of SiO₂ surfaces after biomolecule immobilization using techniques already employed in the microelectronic industry are presented and discussed. Optical and spectrophotometric analysis revealed the preservation of biomolecules’ activity once they are anchored on the biointerface.

A nanometric hybrid system consisting of a Fe₃O₄ magnetic nanoparticles modified through the growth of Fe-based Metal-organic frameworks of the MIL (Materials Institute Lavoiser) was developed. The obtained system retains both the nanometer dimensions and the magnetic properties of the Fe₃O₄ nanoparticles and possesses increased the loading capability due to the highly porous Fe-MIL. It was tested to load, carry and release temozolomide (TMZ) for the treatment of glioblastoma multiforme one of the most aggressive and deadly human cancers. The chemical characterization of the hybrid system was performed through various complementary techniques: X-ray-diffraction, thermogravimetric analysis, FT-IR and X-ray photoelectron spectroscopies. The nanomaterial showed low toxicity and an increased adsorption capacity compared to bare Fe₃O₄ magnetic nanoparticles (MNPs). It can load about 12 mg/g of TMZ and carry the drug into A172 cells without degradation. Our experimental data confirm that, after 48 h of treatment, the TMZ-loaded hybrid nanoparticles (15 and 20 μg/mL) suppressed human glioblastoma cell viability much more effectively than the free drug. Finally, we found that the internalization of the MIL-modified system is more evident than bare MNPs at all the used concentrations both in the cytoplasm and in the nucleus suggesting that it can be capable of overcoming the blood-brain barrier and targeting brain tumors. In conclusion, these results indicate that this combined nanoparticle represents a highly promising drug delivery system for TMZ targeting into cancer cells.

Nowadays, agro-food by-products represent a potential low-cost source of biologically active ingredients which have been paid significant attention as nutraceuticals, medicine, food and cosmetics. In a previous study we evaluated the total sugars, metals and polyphenols of olive mill wastewater (OMWW) from a Cerasuola olive cultivar. In the present work we selectively recovered a sugar and mineral enriched fraction (SMEF) from Cerasuola OMWW by a green adsorption/desorption process. The SMEF was mainly found to be composed of monosaccharides and potassium by HPLC-ELSD and ICP-MS. The in vitro cytotoxicity on human fibroblasts, at different concentrations of the fraction, was investigated by MTT and comet assays. In addition, intracellular reactive oxygen species (ROS) production, apoptosis and cell morphological changes were examined. The physical stability of a formulation containing the SMEF (1% w/w) and its in vivo skin effects were also assessed.Our results highlighted that the SMEF showed a toxic effect at higher concentrations (i.e. cell viability reduction, DNA fragmentation and morphological alterations) well correlated with high ROS levels. Conversely, at low concentrations (0.5% and 1% w/w), no significant changes were observed. For the first time, through stability studies and in vivo tests, we also demonstrated that the SMEF formulation is stable and safe for topical application, since skin hydration improvement without negative effects was observed after 7 days of its use. Therefore, the SMEF has great potential to be used for cosmeceutical applications.

Brain and other nervous system cancers are the 10th leading cause of death worldwide. Genome instability, cell cycle deregulation, epigenetic mechanisms, cytoarchitecture disassembly, redox homeostasis as well as apoptosis are involved in carcinogenesis. A diet rich in fruits and vegetables is inversely related with the risk of developing cancer. Several studies report that cruciferous vegetables exhibited antiproliferative effects due to the multi-pharmacological functions of their secondary metabolites such as isothiocyanate sulforaphane deriving from the enzymatic hydrolysis of glucosinolates. We treated human astrocytoma 1321N1 cells for 24 h with different concentrations (0.5, 1.25 and 2.5% v/v) of sulforaphane plus active myrosinase (Rapha Myr^®) aqueous extract (10 mg/mL). Cell viability, DNA fragmentation, PARP-1 and γH2AX expression were examined to evaluate genotoxic effects of the treatment. Cell cycle progression, p53 and p21 expression, apoptosis, cytoskeleton morphology and cell migration were also investigated. In addition, global DNA methylation, DNMT1 mRNA levels and nuclear/mitochondrial sirtuins were studied as epigenetic biomarkers. Rapha Myr^® exhibited low antioxidant capability and exerted antiproliferative and genotoxic effects on 1321N1 cells by blocking the cell cycle, disarranging cytoskeleton structure and focal adhesions, decreasing the integrin α5 expression, renewing anoikis and modulating some important epigenetic pathways independently of the cellular p53 status. In addition, Rapha Myr^® suppresses the expression of the oncogenic p53 mutant protein. These findings promote Rapha Myr^® as a promising chemotherapeutic agent for integrated cancer therapy of human astrocytoma.