Twenty-four hours after the incubation of Raw 264.7 cells with
0.4 lg/ml of LPS, 50 microliters (uL) of sample aliquots were
mixed with 50 microliters (uL) of Griess reagent in 96-well
plates and incubated at room temperature for 15 min. The
absorbance (520 nm) of the mixture was measured on a
microplate reader. The concentration of nitrite was calculated
with the linear equation derived fromthe standard curve generated
by known concentrations of sodium nitrite.