Sonication of smoke tree extract-loaded liposomes: the antioxidant potential of particles

With the aim to examine the radical scavenging activity of smoke tree extract-loaded liposomal particles before and after ultrasound exposure (45 or 70% amplitude and 15 or 30 min), ABTS and DPPH tests were employed. The antioxidant activity of the pure extract was 11.37 ± 0.52 μmol Trolox equivalent (TE)/mL and 79.7 ± 0.5%. Multilamellar liposomes with extract showed significantly higher antioxidant activity in both assays (12.02 ± 0.54 μmol TE/mL and 81.9 ± 0.4%) compared to sonicated liposomes (10.75-11.00 μmolTE/mL and 79.3-80.9%) and pure extract. There was no significant difference between the ABTS radical scavenging activity of the liposomes treated by different amplitudes and times, while prolonged sonication and a higher amplitude caused a significant drop in the anti-DPPH capacity of extract-loaded liposomal vesicles. The presented results and the differences between the obtained data provide a good insight into the overall antioxidant capacity of smoke tree extract-loaded multilamellar and sonicated unilamellar liposomal vesicles.