The increasing demand for innovative approaches in wound healing and skin regeneration has prompted extensive research into advanced biomaterials. This review focuses on showcasing the unique properties of sustainable silk-based particulate systems in promoting the controlled release of pharmaceuticals and bioactive agents in the context of wound healing and skin regeneration. Silk fibroin and sericin are derived from well-established silkworm production and constitute a unique biocompatible and biodegradable protein platform for the development of drug delivery systems. The controlled release of therapeutic compounds from silk-based particulate systems not only ensures optimal bioavailability but also addresses the challenges associated with conventional delivery methods. The multifaceted benefits of silk proteins, including their inherent biocompatibility, versatility, and sustainability, are explored in this review. Furthermore, the intricate mechanisms by which controlled drug release takes place from silk-based carriers are discussed.

Colloidal gels assembled from gelatin nanoparticles (GNPs) as particulate building blocks show strong promise to solve challenges in cell delivery and biofabrication, such as low cell survival and limited spatial retention. These gels offer evident advantages to facilitate cell encapsulation, but research on this topic is still limited, which hampers our understanding of the relationship between the physicochemical and biological properties of cell-laden colloidal gels. Human adipose-derived mesenchymal stem cells were successfully encapsulated in gelatin colloidal gels and evaluated their mechanical and biological performance over 7 days. The cells dispersed well within the gels without compromising gel cohesiveness, remained viable, and spread throughout the gels. Cells partially coated with silica were introduced into these gels, which increased their storage moduli and decreased their self-healing capacity after 7 days. This finding demonstrates the ability to modulate gel stiffness by incorporating cells partially coated with silica, without altering the solid content or introducing additional particles. Our work presents an efficient method for cell encapsulation while preserving gel integrity, expanding the applicability of colloidal hydrogels for tissue engineering and bioprinting. Overall, our study contributes to the design of improved cell delivery systems and biofabrication techniques.

A vacinação é um dos métodos mais adequado para proteger a população em geral de infeções. No entanto, a contínua evolução e a resistência dos microrganismos aos métodos atualmente existentes traduz-se na necessidade de inovar nesta área. A imunização através das mucosas, particularmente por via intranasal, apresenta diversas vantagens, relativamente à imunização por outras vias, particularmente no que concerne à potenciação da resposta imunológica, sendo um tema amplamente estudado por vários investigadores. Na presente dissertação é analisada a influência de diversos sistemas coloidais na encapsulação de antigénios e/ou adjuvantes utilizados para a imunização intranasal. Os estudos in vivo mais recentes envolvendo nanopartículas, micelas, lipossomas, arqueossomas, nanotubos de carbono ou partículas ‘virus-like’ são apresentados, bem como as barreiras fisiológicas, farmacêuticas e regulamentares que estes sistemas têm que ultrapassar para atingirem o sucesso no mercado e na adesão da população.