Figure 9: Inhibition of NBT reduction of free quercetin, free catechin, quercetin-loaded PLGA nanoparticles, and catechin-loaded PLGA nanoparticles at three different concentrations (7, 21, and 35 μM). All results are expressed as mean ± SE of three repetitions with at least two replicates. and significantly different ( 𝑃 < 0 . 5 ) from free flavonoids (positive control) and free PLGA NPs (negative control).