Briefly, 150 mLof fluorescein
(20 nmol/L) was added to the designated wells of a 96-wells black
plate, followed by the addition of 25 mL of blank, standard (Trolox
25e100 mmol/L) or samples to the designated wells. The plate was
incubated at 37 C for 30 min in Microplate Reader (Biotek In-
struments,Winooski, VT, USA). Then, 25 mL of freshly prepared 2, 20
Azobis (2-methylpropionamidine) dihydrochloride (153 mmol/L)
was added to all the designated wells. Fluorescence was monitored
using 485 nm excitation and 528 nm emissions at 2 min intervals
for 180 min.