Zein-based smart coatings for drug-eluting stents: investigations via static and microfluidic approaches

Coronary heart disease is currently responsible for a significant percentage of global mortality in developed and developing nations alike. This occurrence takes place despite the advancement in medical technology and improved treatment options, such as stenting procedures. Due to complications with restenosis and stent thrombosis that are associated with current commercial stents, there has been a growing interest in stent research and development in order to eradicate the causes of such clinical events. The selection of an antioxidant, non-thrombogenic coating has been a major obstacle to the development of drug-eluting stents (DES), and, to date, a truly biocompatible stent platform remains elusive. Moreover, there is a need to assess stent coatings within an in vitro platform prior to in vivo and clinical studies in order to minimize adverse effects. Even if considerable progress has been made over the last two decades in the development of flow chambers to monitor and study thrombus formation outside of the circulation, blood-material interactions are still little investigated under static and dynamic modes. In order to avoid some of the drawbacks of synthetic polymers, such as their undesirable degradation products, long-lasting presence, or potential biocompatibility issues, the aim of this PhD thesis was to investigate zein as a green and abundant plant-derived protein as a coating material for DES applications. This study aimed to understand the potential uses of zein as a controlled release matrix for drug delivery systems, in addition to developing a microfluidic platform to assess the behavior and hemocompatibility of the proposed plant-based stent coatings under flow conditions

Hydroxycinnamic Acids and Derivatives Formulations for Skin Damages and Disorders: A Review

Alterations of skin homeostasis are widely diffused in our everyday life both due to accidental injuries, such as wounds and burns, and physiological conditions, such as late-stage diabetes, dermatitis, or psoriasis. These events are locally characterized by an intense inflammatory response, a high generation of harmful free radicals, or an impairment in the immune response regulation, which can profoundly change the skin tissue’ repair process, vulnerability, and functionality. Moreover, diabetes diffusion, antibiotic resistance, and abuse of aggressive soaps and disinfectants following the COVID-19 emergency could be causes for the future spreading of skin disorders. In the last years, hydroxycinnamic acids and derivatives have been investigated and applied in several research fields for their anti-oxidant, anti-inflammatory, and anti-bacterial activities. First, in this study, we give an overview of these natural molecules’ current source and applications. Afterwards, we review their potential role as valid alternatives to the current therapies, supporting the management and rebalancing of skin disorders and diseases at different levels. Also, we will introduce the recent advances in the design of biomaterials loaded with these phenolic compounds, specifically suitable for skin disorders treatments. Lastly, we will suggest future perspectives for introducing hydroxycinnamic acids and derivatives in treating skin disorders

Polysaccharide-protein microparticles based-scaffolds to recover soft tissue loss in mild periodontitis

: Periodontal regeneration is extremely limited and unpredictable due to structural complications, as it requires the simultaneous restoration of different tissues, including cementum, gingiva, bone, and periodontal ligament. In this work, spray-dried microparticles based on green materials (polysaccharides - gums - and a protein - silk fibroin) are proposed to be implanted in the periodontal pocket as 3D scaffolds during non-surgical treatments, to prevent the progression of periodontal disease and to promote the healing in mild periodontitis. Arabic or xanthan gum have been associated to silk fibroin, extracted from Bombyx mori cocoons, and loaded with lysozyme due to its antibacterial properties. The microparticles were prepared by spray-drying and cross-linked by water vapor annealing, inducing the amorphous to semi-crystalline transition of the protein component. The microparticles were characterized in terms of their chemico-physical features (SEM, size distribution, structural characterization - FTIR and SAXS, hydration and degradation properties) and preclinical properties (lysozyme release, antibacterial properties, mucoadhesion, in vitro cells adhesion and proliferation and in vivo safety on a murine incisional wound model). The encouraging preclinical results highlighted that these three-dimensional (3D) microparticles could provide a biocompatible platform able to prevent periodontitis progression and to promote the healing of soft tissues in mild periodontitis