**12. Enhanced stability**

The instability of most phytochemicals in bio environments results in quick degradation and reduced activity. Encapsulation of such phytochemicals in carriers shields them from harsh conditions that lead to their decomposition. Quercetin has a life time of only five minutes in plasma whereas; quercetin loaded in liposomes modified with polyethylene glycol (PEG) has a life time of more than five hours in plasma [73]. Quercetin was also encapsulated in polymeric nanoparticles. Its antioxidant activity was maintained while its stability was highly enhanced when encapsulated in eudragit nanoparticles (polymeric nanoparticles). This polymeric nanoparticle protected quercetin and improved its stability in in acidic medium. However, the polymeric nanoparticles released the antioxidant under neutral to basic conditions, making such nanoparticles suitable for oral delivery of bioactive compounds and deliver them beyond the acidic stomach environment [74].
