Quercetin loaded nanoformulations for therapeutic purposes: a review

Quercetin (Q) is a natural polyphenolic flavonoid compound present in a variety of food plants such as onions, tomatoes, apples, green vegetables, beans and other dietary sources. It is known that quercetin has numerous nutraceutical properties. However, its oral delivery continues to be a barrier due to its low bioavailability. Thus, the incorporation of quercetin in a drug delivery system has been considered a promising alternative for oral administration of this compound. This review includes articles from the National Library of Medicine (MedLine), Scopus and Web of Science databases, using descriptors and search strategy, “nanoformulation” OR “nanoparticles” AND “quercetin” AND “effects”. Taken together, the results of these studies have provided an understanding of the biological action of quercetin and of its functional effects such as antioxidant, anti-cancer, and anti-toxic. The present review allows an analysis of the benefits of quercetin in health, and whether these could be further improved if quercetin was incorporated into a nanostructure, solving problems related to its bioavailability.