Plant-Based Flavones of Therapeutic Interest Loaded into Polymeric Nanoparticles

Background/Objectives: Flavonoids are low-molecular-weight polyphenolic compounds that are universally distributed in plants. They are a chemically varied group of secondary metabolites with a broad range of biological activity. The use of flavonoids is known to decrease the risk of many chronic diseases due to their radical scavenging, antioxidant, anti-inflammatory, anticarcinogenic, and antimutagenic properties. Limitations in the use of flavonoids include their low water solubility and poor stability, and therefore their low bioavailability. The encapsulation of flavonoids in different nanocarriers has helped to overcome this limitation. Taking this into account, in this work, the encapsulation of four flavones with several therapeutic applications-7-hydroxyflavone, 7,8-dihydroxyflavone, baicalein, and luteolin-in poly(lactic-co-glycolic) acid (PLGA)-derived polymeric nanoparticles (NPs) has been investigated. Methods: A physicochemical characterization of the NPs has been carried out using different techniques, including the evaluation of antioxidant and antimicrobial activities. Results: In all cases, the encapsulation efficiency of the four flavones in the prepared NPs was high (>90%), the zeta potential was about -31 mV, and the size was nanometric (~450 nm). The drug release from the nanoparticles was also studied, showing first-order kinetics. Statistical tools were applied to the release rate constants. The antioxidant activity and the in vitro antimicrobial activity of the free and flavone-loaded NPs were investigated, in the case of the latter using Gram-positive and Gram-negative bacteria. Results show that when the flavones are encapsulated, they retain their therapeutic properties. Conclusions: In summary, PLGA-based NPs not only prevent flavone degradation but also significantly boost solubility, ultimately optimizing bioavailability. Our results underscore these NPs as a promising platform for efficient flavone delivery.