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Hospitals serve as critical environments for the management of diverse medical conditions, ranging from routine illnesses to life-threatening emergencies. However, alongside providing healthcare services, hospitals represent reservoirs for the transmission of microbial pathogens. Understanding the distribution and dynamics of pathogens within hospital settings is crucial for effective infection control and prevention strategies. Concurrently, the integration of cutting-edge technologies for the early detection and monitoring of target bacteria stands as a pivotal strategy in this battle against nosocomial infections. This critical review aims to provide a systematic insight into the main threatening microbes in hospitals and the detection of pathogens in different environments, ranging from intensive care units to general wards, including hospital entrances, bathrooms, high-touch surfaces, patient bed rails, medical equipment, and floors, which are often contaminated. We discuss recent scientific and technological advances in pathogen detection by exploring innovative methods that leverage nanotechnology to improve biosensing effectiveness and selectivity. This review is divided into sections focusing on various types of hospital environments, classes of mostly represented pathogens and kinds of available nanobiosensors. We include two comprehensive tables summarizing bacterial contamination in hospital wards and the materials and substrates associated with the nanobiosensors that have been developed. Eventually, we highlight the open challenges and perspectives in nanotechnology-based healthcare-environment monitoring and remediation as a promising solution to counteract pathogen emergence and spread.

The use of co-processed materials for Orally Disintegrating Tablets (ODT) preparation by direct compression is well consolidated. However, the evaluation of their potential for ODT preparation by 3D printing technology remains almost unexplored. The present study aimed to estimate the use of commercially available co-processed excipients, conventionally applied in compression protocols, for the preparation of ODTs with binder jetting-3D printing technology. The latter was selected among the 3D printing techniques because the deposition of multiple powder layers allows for obtaining highly porous and easily disintegrating dosage forms. The influence of some process parameters, including layer thickness, type of waveform and spread speed, on the physical and mechanical properties of the prototypes printed were evaluated. Our results suggested that binder jetting-3D printing technology could benefit from the co-processed excipients for the preparation of solid dosage forms. The process optimization conducted with the experiments reported in this work indicated that additional excipients were needed to improve the physical properties of the resulting ODTs.

Nanomedicine provides various opportunities for addressing medical challenges associated with drug bioavailability, stability, and efficacy. In particular, oral nanoparticles (NPs) represent an alternative strategy to enhance the solubility and stability of active ingredients through the gastrointestinal tract. The nanocarriers could be used for both local and systemic targeting, enabling controlled release of encapsulated drugs. This approach allows more efficient therapies. In this work, we aim to develop reliable oral solid dosage forms incorporating NPs produced by either one pot synthesis or continuous production, following protocols that yield highly consistent outcomes, promoting their technology transfer and clinical use. Microfluidics technology was selected to allow an automated and highly productive synthetic approach suitable for the highly throughput production. In particular, innovative systems, which combine advantage of NPs and solid dosage formulation, were designed, developed, and characterized demonstrating the possibility to obtaining oral administration. The resulting NPs were thus carried on oral dosage forms, i.e., pellets and minitablets. NPs resulted stable after dosage forms manufacturing, leading to confidence also on protection of encapsulated drugs. Indomethacin was used as a tracer to test biopharmaceutical behaviour. Anti-inflammatories or cytotoxic chemotherapeutics could be vehiculated leading to a breakthrough in the treatment of severe diseases allowing the oral administration of these drugs. We believe that the advancement achieved with the results of our work paves the way for the progression of nanoproducts into clinical transition processes.

The stellar evolution and chemical make-up of the Universe are determined by nuclear reactions occurring in a wide variety of stellar sites. Precise determinations of the cross sections of these reactions are crucial for the calculation of reaction rates and for the development of stellar evolution models. The Laboratory for Underground Nuclear Astrophysics (LUNA) collaboration has been at the forefront of the direct measurement of nuclear reactions at the low energies of astrophysical interest for the last 35 years. The many significant results achieved at LUNA have been made possible due to the low background conditions uniquely available thanks to its location deep underground at the Laboratori Nazionali del Gran Sasso. Another key aspect of these successes is due to the experience of the LUNA collaboration in the production and characterization of a variety of solid targets used in reaction measurements. In this review, the main production techniques of solid targets are described, as well as the common methods adopted for target degradation monitoring. We also present the results of recent measurements using these targets and the future plans of the LUNA collaboration for measurements using solid targets at the LUNA400 kV and the new Ion Beam Facility (IBF) 3.5 MV are also presented.

Brain metastasis (BM) represents a clinical challenge for patients with advanced HER2 + breast cancer (BC). The monoclonal anti-HER2 antibody trastuzumab (TZ) improves survival of BC patients, but it has low central nervous system penetrance, being ineffective in treating BM. Previous studies showed that ferritin nanoparticles (HFn) may cross the blood brain barrier (BBB) through binding to the transferrin receptor 1 (TfR1). However, whether this has efficacy in promoting the trans-BBB delivery of TZ and combating BC BM was not studied yet. Here, we investigated the potential of HFn to drive TZ brain delivery and promote a targeted antitumor response in a murine model of BC BM established by stereotaxic injection of engineered BC cells overexpressing human HER2. HFn were covalently conjugated with TZ to obtain a nanoconjugate endowed with HER2 and TfR1 targeting specificity (H-TZ). H-TZ efficiently achieved TZ brain delivery upon intraperitoneal injection and triggered stable targeting of cancer cells. Treatment with H-TZ plus docetaxel significantly reduced tumor growth and shaped a protective brain microenvironment by engaging macrophage activation toward cancer cells. H-TZ-based treatment also avoided TZ-associated cardiotoxicity by preventing drug accumulation in the heart and did not induce any other major side effects when combined with docetaxel. These results provided in vivo demonstration of the pharmacological potential of H-TZ, able to tackle BC BM in combination with docetaxel. Indeed, upon systemic administration, the nanoconjugate guides TZ brain accumulation, reduces BM growth and limits side effects in off-target organs, thus showing promise for the management of HER2 + BC metastatic to the brain.

The vault nanoparticle is a eukaryotic assembly consisting of 78 copies of the 99-kDa major vault protein. They generate two cup-shaped symmetrical halves, which in vivo enclose protein and RNA molecules. Overall, this assembly is mainly involved in pro-survival and cytoprotective functions. It also holds a remarkable biotechnological potential for drug/gene delivery, thanks to its huge internal cavity and the absence of toxicity/immunogenicity. The available purification protocols are complex, partly because they use higher eukaryotes as expression systems. Here, we report a simplified procedure that combines human vault expression in the yeast Komagataella phaffii, as described in a recent report, and a purification process we have developed. This consists of RNase pretreatment followed by size-exclusion chromatography, which is far simpler than any other reported to date. Protein identity and purity was confirmed by SDS-PAGE, Western blot and transmission electron microscopy. We also found that the protein displayed a significant propensity to aggregate. We thus investigated this phenomenon and the related structural changes by Fourier-transform spectroscopy and dynamic light scattering, which led us to determine the most suitable storage conditions. In particular, the addition of either trehalose or Tween-20 ensured the best preservation of the protein in native, soluble form.

The delivery of therapeutics across the cell membrane and into the cytoplasm is a major challenge that limits the development of new therapies. This challenge is compounded by the lack of a general assay for cytosolic delivery. Here we develop this assay based on the pro-fluorophore CrAsH-EDT2, and provide cytosolic penetration results for a variety of drug delivery agents (polyethyleneimine, poly-arginine, Ferritin, poly [maleic anhydride-alt-isobutene] grafted with dodecylamine, and cationic liposomes) into HeLa and T98G cells. Our results show that this method can be widely applicable to different cells and drug delivery agents, and yield statistically robust results. We later use this method to optimize and improve a model drug delivery agent's (Ferritin) cytosolic penetration.

Il cancro è una delle principali cause di morte nel mondo e glioblastoma e tumore al seno triplo negativo sono due tipologie di tumore caratterizzate da una prognosi sfavorevole e da un alto rischio di recidive. I trattamenti farmacologici oggi a disposizione non sono sufficienti all’ottenimento di una guarigione completa sia a causa della bassa selettività che impedisce l’utilizzo di dosaggi più elevati, sia a causa dello sviluppo di meccanismi di resistenza da parte delle cellule tumorali. In questo contesto le nanoparticelle possono essere sviluppate sia come nuovi trattamenti terapeutici sia per superare alcune limitazioni delle terapie convenzionali. In questo progetto di tesi, ho scelto di utilizzare nanoparticelle di H-ferritina (HFn), una forma ricombinante di ferritina che possiede alcune caratteristiche che la rendono un buon candidato per migliorare i trattamenti terapeutici già disponibili per questi due tumori. L’HFn è infatti biocompatibile, la sua cavità interna può essere utilizzata per il caricamento di farmaci e molecole di detection e la sua superficie può essere facilmente modificata sfruttando i numerosi gruppi funzionali esposti verso l’esterno. La HFn è, inoltre, in grado di legarsi al recettore della transferrina (TfR1), over-espresso dal 98% dei tumori solidi. Tale recettore è over espresso anche dalle cellule endoteliali che compongono la barriera ematoencefalica, rendendo così la HFn in grado di attraversarla. Il mio lavoro di tesi può essere suddiviso in due progetti. Nel primo progetto i gruppi funzionali esposti sulla superficie della HFn sono stati utilizzati per la coniugazione dell’anticorpo monoclonale cetuximab al fine di studiare il mantenimento della sua attività antitumorale in modelli tumorali 3D e di paragonarla a quella del cetuximab non coniugato. Come modelli tumorali 3D sono stati utilizzati sferoidi ottenuti da una linea cellulare di glioblastoma e da una di tumore al seno triplo negativo. Sulla base dei prom, Cancer is a leading cause of disease worldwide and glioblastoma and triple negative breast cancer represent two types of tumors with poor prognosis and a high risk of recurrence. The therapeutic options currently in use are still subject to failure, due to (1) the poor selectivity of drugs, which compromises dose escalation to more therapeutically active levels and (2) the development of resistance by different mechanisms that cells put in place to defend themselves from the action of drugs. In this scenario, nanoparticles can be developed as new therapeutic strategies or to overcome the limitations of the treatments currently in use. In my PhD project, I exploited the unique features of a nanoparticle-based on recombinant heavy-chain ferritin cages (HFn) to improve the therapeutic treatments already available for these tumors. HFn can be a promising candidate for this study because 1) it is biocompatible; 2) it can be loaded with drugs; 3) it can be easily modified by exploiting the functional groups on its surface; 4) it exhibits tumor targeting by recognition of TfR1, overexpressed in 98% of human cancers and directly correlated with tumor stage or cancer progression; 5) HFn is able to cross the blood-brain barrier (BBB) exploiting the same TfR1 receptor, also found overexpressed on the BBB endothelial wall. My work is divided into two main subprojects, all sharing the use of HFn. In the first subproject (chapter one), the functional groups present on the surface of HFn were exploited for the conjugation of the monoclonal antibody cetuximab, studying the maintenance of its anticancer activity against a 3D tumor model in comparison with unconjugated cetuximab. Cancer spheroids of glioblastoma and triple negative breast cancer were selected and produced for this study. Then we focused on the documented ability of cetuximab to promote an indirect anticancer effect (ADCC) through the activation of immune systems cells. ADCC activation was evaluated both in live imagi

This work originated from the need to functionalize surfactant-coated inorganic nanoparticles for biomedical applications, a process that is limited by excess unbound surfactant. These limitations are connected to the bioconjugation of targeting molecules that are often in equilibrium between the free aliquot in solution and that which binds the surface of the nanoparticles. The excess in solution can play a role in the biocompatability in vitro and in vivo of the final nanoparticles stock. For this purpose, we tested the ability of common surfactants - monothiolated polyethylene glycol and amphiphilic polymers - to colloidally stabilize nanoparticles as excess surfactant is removed and compared them to newly appearing multidentate surfactants endowed with high avidity for inorganic nanoparticles. Our results showed that monothiolated polyethylene glycol or amphiphilic polymers have an insufficient affinity to the nanoparticles and as the excess surfactant is removed the colloidal stability is lost, while multidentate high-avidity surfactants excel in the same regard, possibly allowing improvement in an array of nanoparticle applications, especially in those stated.