Quercetin-Based Advanced Delivery Systems – From Multimodal Nano-theranostics to Microneedles: a Recent Update on Their Preclinical Studies

Quercetin, a naturally derived flavonoid, shows promise for its anticancer, antimicrobial, anti-inflammatory, and antioxidant properties, but its clinical use is limited by poor solubility and bioavailability. Recent advancements in delivery systems, such as nanoencapsulation, polymeric carriers, and microneedle scaffolds, aim to enhance its stability and targeted delivery. Traditional theranostic systems face challenges like biocompatibility and cost, but quercetin-based platforms offer a promising alternative. This review explores the design strategies and biomedical applications of quercetin-based theranostics, highlighting challenges like controlled delivery and validation in animal studies, and suggests future directions for these emerging systems.