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Acid catalysis is recognised as the most reliable industrial ì way to convert hydrocarbons into various products (methanol to olefins and aromatics, glycerol to olefins, methane dehydroaromatization, isomerization, etc.). In this concern, ZSM-5 is extensively used, also because of peculiar type of active sites of such zeolite. In this paper, a fine tuning of the acidity content and strength of ZSM-5 was investigated through a combination of post- synthesis treatments: desilication via alkaline solution and wet impregnation with Mg2+ions followed by calcination. Results show that the insertion of Mg2+has a large influence on the distribution and strength of Brønsted and Lewis acid sites of the hierarchical ZSM-5, as well as an improved crystallinity with respect to the desilicated-one. The hierarchical ZSM-5 zeolite incorporating Mg-species was tested in Methanol- to-olefins reaction and the reduction of acid strength of catalyst increased the selectivity toward light olefins (mainly propylene) as well as it suppressed oligomerisation reactions delaying the coke formation.

The modification of the physicochemical properties of synthetic zeolites is an important element when these materials are applied as heterogeneous catalysts in the view of more sustainable and effective processes. In this work, desilicated ZSM5 samples were tested on the methanol to dimethyl ether dehydration. Desilication time strongly affects the textural and acidic properties of the samples, and those characteristics determined a different catalytic behaviour. Contact time of 60 min with NaOH solution (alkaline desilication) favourably impact on the activity of the catalysts and its stability against deactivation in terms of methanol conversion and yield to DME, in comparison with parent zeolite and sample prepared after 30 min of desilication. This effect is due to a combination of changes in the properties of acidic sites and mesoporous volume, as confirmed by stability test over 80 h of reaction. The analysis of formed coke confirmed this evidence since the most performing catalyst showed the lowest tendency to form coke as the main consequence of the improved accessibility to the acid sites determined by the induced mesoporosity.

Buccal mucosa has emerged as an attractive site for systemic administration of drug in paediatric patients. This route is simple and non-invasive, even if the saliva wash-out effect and the relative permeability of the mucosa can reduce drug absorption (Lam et al., 2014). Mucoadhesive polymers represent a common employed strategy to increase the contact time of the formulation at the application site and to improve drug absorption. Among the different mucoadhesive dosage forms, buccal films are particularly addressed for paediatric population since they are thin, adaptable to the mucosal surface and able to offer an exact and flexible dose (Borges et al., 2015; Trastullo et al., 2016). The objective of the present study was to develop bilayered buccal films for the release of propranolol hydrochloride, a non-selective β1 and β2 adrenergic antagonist, indicated in paediatrics for the treatment of hypertension. Mucoadhesive layer was prepared by casting and drying of solutions of film-forming polymers, such as polyvinylpyrrolidone (PVP) or polyvinylalcohol (PVA), added with different weight ratios of gelatin (GEL) or chitosan (CH). In order to achieve unidirectional drug delivery towards buccal mucosa, an ethylcellulose coating layer was applied onto the first one. Bilayered films were characterized for their physico-chemical and functional properties. The inclusion of CH into PVP and PVA films provided the best mucoadhesion ability, probably due to their highest hydration among all the formulations, that ensured a good interpenetration and entanglement between polymer and mucin chains. Moreover, the positively charged ammino groups of CH could interact with negatively charged sialic acid and sulphate residues of mucin glycoprotein. Films containing CH provided a lower drug release with respect to films containing GEL, due to their lower viscosity in the gelled state which limited drug diffusion. The presence of CH also increased the amount of permeated drug through buccal mucosa, thanks to its ability of interfering with the lipid organization. Coating layer did not interfere with drug permeation, but it could limit drug release in the buccal cavity. With polymeric films, a novel solid buccal formulation was developed. The selection of suitable polymeric mixture allowed the modulation of the mucoadhesive ability, the release of the drug and its permeation through the buccal mucosa. Moreover, polymeric films fulfill all current demands for child-appropriate dosage forms. In fact, they combine the convenience of tablets, a solid dosage form, with less issues instability than liquid formulations, and the opportunity to avoid swallowing of a large unit. Moreover, the use of films with different sizes enables the administration of variable doses of drug and can be suitable for a large range of age groups. Borges A.F., Silva C., Coelho J.F., Simões S. Oral films: current status and future perspectives. I – Galenical development and quality attributes. J. Control. Release 206 (2015) 1-19. Lam J.K., Xu Y., Worsley A., Wong I.C. Oral transmucosal drug delivery for pediatric use. Adv. Drug Deliv. Rev. 73 (2014) 50-62. Trastullo R., Abruzzo A., Saladini B., Gallucci M.C., Cerchiara T., Luppi B., Bigucci F. Design and evaluation of buccal films as paediatric dosage form for transmucosal delivery of ondansetron. Eur. J. Pharm. Biopharm. 105 (2016) 115-121.

Bifidobacteria are predominant microorganisms in the intestinal flora, but at the same time represent a subdominant group of the vaginal microbiota. For this reason, oral administration of these probiotic bacteria can provide beneficial effect for both intestinal and urogenital ecosystems. The first aim of this study was to test the strain Bifidobacterium breve BC204, isolated from a vaginal swab of a healthy woman, for its capability to adhere to human cells, to survive to gastric acids and bile salts and to exert antimicrobial activities. The second aim of the work was to develop an oral formulation able to guarantee bacterial survival during storage and administration, thus favouring intestinal and vaginal colonization. B. breve BC204 was encapsulated by spray-drying and subsequently formulated in time-dependent erodible tablets. B. breve BC204 showed good ability to adhere to Caco-2 cells and moderate ability to resist to gastrointestinal stress. Moreover, it exerted a strong antimicrobial activity against urogenital and enteric pathogens. Microencapsulation followed by tablet production allowed high loading and survival of B. breve BC204, associated to a delayed release and mucoadhesive ability. These characteristics are required to achieve appropriate amount and persistence of viable microbial cells in the treatment site.

In this work, we propose as new wound dressing, the Spanish Broom fibers impregnated with vancomycin (VM) loaded chitosan nanoparticles. Spanish Broom fibers were extracted by patented method DiCoDe and the morphological, physical and mechanical properties were investigated. Chitosan nanoparticles were prepared by ionic gelation using different weight ratios between chitosan (CH) and tripolyphosphate (TPP). Nanoparticles were characterized in terms of size, zeta potential, yield, encapsulation efficiency, stability and drug release. Finally, the antibacterial activity against Staphylococcus aureus as well as in vitro cytotoxicity on HaCaT cells were evaluated. The best formulation CH/TPP 4:1 was selected based on the encapsulation efficiency and yield. Spanish Broom fibers impregnated with loaded nanoparticles showed an increased antibacterial activity against S . aureus compared to the same fibers containing VM without nanoparticles. Moreover, these fibers were not toxic to HaCaT keratinocytes cells. In conclusion, Spanish Broom fibers impregnated with VM loaded CH/TPP nanoparticles would appear to be a promising candidate for wound dressing application.

This paper presents a fully integrated step-up switched-capacitor DC-DC converter for energy harvesting applications. The proposed solution exhibits both a high voltage-conversion ratio and a high power-conversion efficiency from a low-voltage source such as a thermoelectric generator or an indoor solar cell. The circuit has been implemented in TSMC 55nm CMOS process. Measurements demonstrate that it can properly operate with a 220 mV input, providing a 1.9 V output voltage at 10.45 μW output power, with 37.4% power conversion efficiency. We demonstrate that it can be used as a power supply for a Bluetooth Low Energy beacon with a thermoelectric generator subjected to a temperature difference of only 3.5°C.

The aim of this work was to develop a synbiotic vaginal insert containing the probiotic strain Lactobacillus crispatus BC5, the prebiotic substrate fructo-oligosaccharide and the antioxidant agent ascorbic acid, for the prophylaxis and therapy of vaginal infections. Mucoadhesive in situ gelling vaginal inserts based on hydroxypropyl methylcellulose were prepared by freeze-drying, stored at +2-8 °C for 90 days and characterized in terms of technological and functional properties. Complete survival of L. crispatus BC5 was found immediately after insert preparation (96.08%) as well as after 90 days of storage (95.82%) in the vaginal inserts containing fructo-oligosaccharide, ascorbic acid and skimmed milk. Synbiotic inserts showed improved mucoadhesion ability (from three- to five-fold) with respect to a standard formulation based on hydroxypropyl methylcellulose alone. Moreover, inserts allowed to modulate lactobacilli release in virtue of the different amounts of fructo-oligosaccharide. Finally, antimicrobial activity was exerted by L. crispatus BC5 released from the vaginal formulation.

This work presents modeling, fabrication and characterization of planar microcoils for wireless power transfer in medical implanted devices, proposing integrated technology as a way to reduce the dimensions and achieve higher efficiency. The wireless power transfer (WPT) architecture is composed by: a primary coil carrying the alternating current signal to generate a magnetic field and the receiving coil to convert magnetic field in current, that is located parallel to the primary one with a gap between the two inductors. In the proposed design the two microcoils are circular with short-circuited turns to minimize electrical resistance. The electrical measurements on the fabricated test structures with different pitch sizes show a dramatic reduction of coil resistance to few ohms with respect to classic coil design. The experimental values of the resistance and inductance (from 24 to 45 nH) are in good agreement with the analytical model. The efficiency of fabricated microcoils for wireless power transfer is predicted by Finite element method (FEM) at 10 kHz modeling in terms of coupling factor ranging the distance of the inductors from 0 to 1 mm. FEM results show that the transfer efficiency can be further enhanced by the introduction of a ferromagnetic material on the back side of each coil in order to confine the magnetic field. High coupling factor above 65% can be achieved with this shielding layer, even with lowest pitch value and high coil distances.

Today, hydrogen is seen as the most convenient energy carrier for a number of applications and, particularly, for proton exchange membrane fuel cells (PEMFCs). In the specialized literature, many studies address the production of hydrogen derived from renewables. Therefore, the scope of this chapter is to review the recent findings about hydrogen generation from reforming processes of bio-sources combined with membrane reactor technology. A deep discussion is presented about the general classification of the membranes, with special attention being paid towards palladium-based membranes. Furthermore, a short overview on the representative results on the reforming of ethanol and methanol as renewable sources performed in membrane reactors is given.