*2.6. Functional Characteristics of Particles*

#### 2.6.1. Photochemical Stability of Quercetin

Photochemical stability of pristine and encapsulated quercetin was evaluated by the procedure presented by Sun et al. [26]. Quercetin dispersed in water and encapsulated in HZ and HZ-chi/pec particles at 5 μg/mL were irradiated up to 120 min with a 365 nm ultraviolet lamp (VWR International Inc., West Chester, PA, USA). Samples were collected at 0, 15, 30, 60, 90 and 120 min, and the content of quercetin was analyzed with the help of UV-Vis spectrophotometer mentioned above in Section 2.3.2.
