Overview of dendrimers as promising drug delivery systems with insight into anticancer and anti-microbial applications.

Dendrimers are tree-like polymeric molecules that have three main compartments: the core, branching units, and functional end groups. They are nanosized and monodispersed, with an almost spherical shape. For the past few decades, dendrimers have been evaluated in numerous studies as a promising category of candidates for gene delivery and diagnostic applications. Nowadays, some advanced dendrimers are considered promising anticancer delivery systems due to the vast types and applicable modifications. They also showed their effectiveness as antibacterial and antiviral agents. Smart dendrimers with pH-, redox-, or directly tumor microenvironment-responsive properties are investigated. pH-sensitive dendrimers enhance drug release in the tumor's acidic environment and inhibit release at physiological pH, thereby increasing the hemocompatibility of these chemical agents. Dendrimers have been examined for years to prevent sexually transmitted diseases, such as HIV, HPV, HSV, etc. In this regard, some studies yielded encouraging results and opened new avenues. Following the onset of the COVID-19 pandemic, researchers have shifted their focus toward seeking remedies to prevent and treat this viral disease. Dendrimers have already demonstrated favorable efficacy in protection against COVID-19 and other respiratory viral diseases. Furthermore, they may mitigate the neuroinflammatory manifestations of COVID-19 in individuals experiencing a critical disease state.