About 80% higher risk of amputation resulting from microbial infection was indicated for patients with diabetic foot ulcers (DFUs). Micro and nano-scaffolds made of natural polymers specifically cellulose, chitosan, and collagen can donate the biocompatibility, biodegradability, and bioavailability properties appropriate to accelerate wound closure before microbial biofilm formation. The antimicrobial activity of these wound dressings can be improved by the incorporation of bioactive compounds extracted from medicinal plant species such as curcumin. Low water solubility and poor bioavailability are recognized as two main disadvantages of curcumin, lipophilic phytopolyphenol, which could be controlled by targeted polymeric micro and nano-scaffolds. Consequently, this review has discussed the capacity and challenges of these types of formulations according to recent investigations.

Quantum dots (QDs) are semiconductor materials that range from 2 to 10 nanometers. These nanomaterials (NMs) are smaller and have more unique properties compared to conventional nanoparticles (NPs). One of the unique properties of QDs is their special optoelectronic properties, making it possible to apply these NMs in bioimaging. Different size and shape QDs, which are used in various fields such as bioimaging, biosensing, cancer therapy, and drug delivery, have so far been produced by chemical methods. However, chemical synthesis provides expensive routes and causes serious environmental and health issues. Therefore, various biological systems such as bacteria, fungi, yeasts, algae, and plants are considered as potent eco-friendly green nanofactories for the biosynthesis of QDs, which are both economic and environmentally safe. The review aims to provide a descriptive overview of the various microbial agents for the synthesis of QDs and their biomedical applications for the diagnosis and treatment of cancer and SARS-CoV-2.