The constant advent of major health threats such as antibacterial resistance or highly communicable viruses, together with a declining antimicrobial discovery, urgently requires the exploration of innovative therapeutic approaches. Nowadays, strategies based on metal nanoparticle technology have demonstrated interesting outcomes due to their intrinsic features. In this scenario, there is an emerging and growing interest in copper-based nanoparticles (CuNPs). Indeed, in their pure metallic form, as oxides, or in combination with sulfur, CuNPs have peculiar behaviors that result in effective antimicrobial activity associated with the stimulation of essential body functions. Here, we present a critical review on the state of the art regarding the in vitro and in vivo evaluations of the antimicrobial activity of CuNPs together with absorption, distribution, metabolism, excretion, and toxicity (ADMET) assessments. Considering the potentiality of CuNPs in antimicrobial treatments, within this Review we encounter the need to summarize the behaviors of CuNPs and provide the expected perspectives on their contributions to infectious and communicable disease management.

Currently, nanomaterials are of widespread use in daily commercial products. However, the most promising and potentially impacting application is in the medical field. In particular, nano-sized noble metals hold the promise to shift the current medical paradigms for the detection and therapy of neoplasms thanks to the: i) localized surface plasmon resonances (LSPRs), ii) high electron density, and iii) suitability for straightforward development of all-in-one nano-platforms. Nonetheless, there is still no clinically approved noble metal nanomaterial for cancer therapy/diagnostic. The clinical translation of noble metal nanoparticles (NPs) is mainly prevented by the issue of persistence in organism after the medical action. Such persistence increases the likelihood of toxicity and the interference with common medical diagnoses. Size-reduction to ultrasmall nanoparticles (USNPs) is a suitable approach to promote metal excretion by the renal pathway. However, most of the functionalities of NPs are lost or severely altered in USNPs, jeopardizing clinical applications. A groundbreaking advance to jointly combine the appealing behaviors of NPs with metal excretion relies on the ultrasmall-in-nano approach for the design of all-in-one degradable nano-platforms comprising USNPs. Such nano-architectures might lead to the delivery of a novel paradigm for nanotechnology, enabling the translation of noble metal nanomaterials to clinics in order to treat carcinomas in a less invasive and more efficient manner. This review covers the recent progresses related to this exciting approach. The most significant nano-architectures designed with the ultrasmall-in-nano approach are discussed, and their applicative perspectives provided.

Nanomaterials have attracted increasing interest for their potentiality to revolutionize the diagnosis and treatment of many diseases, especially neoplasms. Interestingly, there is a huge imbalance between the number of proposed nanoplatforms and the few ones approved for clinical applications. This disequilibrium affects in particular noble metal nanoparticles (NPs), that present no-approved platform and very few candidates in clinical trials because of the issue of persistence. In this perspective, we discuss if nanomedicine is generally keeping its promises with a focus on the approach that could fill the gap between NPs and oncology in the next future: the ultrasmall-in-nano.