Metals in hybrid drug delivery nanosystems: role, applications and perspectives

Hybrid nanosystems have emerged as versatile and advanced platforms for targeted and controlled drug delivery [1]. Metals can play a dual role in multifunctional nanosystems. Specifically, they can be the main backbone of the nanostructure (i.e., gold and silver nanoparticles) or functional components in modified liposomes. Starting from this concept, we recently focused our research on new multifunctional nanomaterials originated by the symbiotic combination of noble mono- and bi-metallic nanoparticles with saccharides (poly--cyclodextrin, chitosan, hyaluronic acid, bacterial exopolysaccharides) (Figure 1A-B) [2,3]. Moreover, we exploited physiologically relevant metal cations (Mn2+, Zn2+, Ca2+) for promoting the active loading of gemcitabine into conventional drug delivery systems (Figure 1C). Within these collaborative projects, the main design criteria used to synthetize symbiotic nanomaterials, their physicochemical properties, intracellular trafficking and biological response have been investigated. Both covalent or supramolecular chemical approaches have been employed pointing out that a proper design of the nanocomposite allows for different and intriguing applications. Taking into account the main outcomes of our scientific runway (2019-2025), promises and limits of hybrid nanosystems as antibacterial nanomedicines, SERS-nanoTag and anticancer nanotherapeutics will be discussed.